Volume I are: Introduction; Classification of Fuels; Impurities

of Coals; Coal Washing; Sampling and Valuation of Coals, etc.; Power of Fuels; History of Coke Manufacture; Developments in the Coke Oven Design; Recent Types of Coke Ovens; Mechanical Appliances at Coke Ovens; Chemical and Physical Examination of Coke. Volume II covers fully the subject of By-Products. Price, per volume =$3.00 net=

~COMPRESSED AIR~

=Compressed Air in All Its Applications.= By GARDNER D. HISCOX.

This is the most complete book on the subject of Air that has ever been issued, and its thirty-five chapters include about every phase of the subject one can think of. It may be called an encyclopedia of compressed air. It is written by an expert, who, in its 665 pages, has dealt with the subject in a comprehensive manner, no phase of it being omitted. Includes the physical properties of air from a vacuum to its highest pressure, its thermodynamics, compression, transmission and uses as a motive power, in the Operation of Stationary and Portable Machinery, in Mining, Air Tools, Air Lifts, Pumping of Water, Acids, and Oils; the Air Blast for Cleaning and Painting the Sand Blast and its Work, and the Numerous Appliances in which Compressed Air is a Most Convenient and Economical Transmitter of Power for Mechanical Work, Railway Propulsion, Refrigeration, and the Various Uses to which Compressed Air has been applied. Includes forty-four tables of the physical properties of air, its compression, expansion, and volumes required for various kinds of work, and a list of patents on compressed air from 1875 to date. Over 500 illustrations, 5th Edition, revised and enlarged.

Cloth bound. Price =$5.00=

Half Morocco. Price =$6.50=

~CONCRETE~

=Concrete Workers' Reference Books. A Series of Popular Handbooks for Concrete Users.= Prepared by A. A. HOUGHTON =50 cents=

_The author, in preparing this Series, has not only treated on the usual types of construction, but explains and illustrates molds and systems that are not patented, but which are equal in value and often superior to those restricted by patents. These molds are very easily and cheaply constructed and embody simplicity, rapidity of operation, and the most successful results in the molded concrete. Each of these books is fully illustrated, and the subjects are exhaustively treated in plain English._

=Concrete Wall Forms.= By A. A. HOUGHTON.

A new automatic wall clamp is illustrated with working drawings. Other types of wall forms, clamps, separators, etc., are also illustrated and explained. (No. 1 of Series) Price =50 cents=

=Concrete Floors and Sidewalks.= By A. A. HOUGHTON.

The molds for molding squares, hexagonal and many other styles of mosaic floor and sidewalk blocks are fully illustrated and explained. (No. 2 of Series) Price =50 cents=

=Practical Concrete Silo Construction.= By A. A. HOUGHTON.

Complete working drawings and specifications are given for several styles of concrete silos, with illustrations of molds for monolithic and block silos. The tables, data, and information presented in this book are of the utmost value in planning and constructing all forms of concrete silos. (No. 3 of Series) Price =50 cents=

=Molding Concrete Chimneys, Slate and Hoof Tiles.= By A. A. HOUGHTON.

The manufacture of all types of concrete slate and roof tile is fully treated. Valuable data on all forms of reinforced concrete roofs are contained within its pages. The construction of concrete chimneys by block and monolithic systems is fully illustrated and described. A number of ornamental designs of chimney construction with molds are shown in this valuable treatise. (No. 4 of Series.) Price =50 cents=

=Molding and Curing Ornamental Concrete.= By A. A. HOUGHTON.

The proper proportions of cement and aggregates for various finishes, also the method of thoroughly mixing and placing in the molds, are fully treated. An exhaustive treatise on this subject that every concrete worker will find of daily use and value. (No. 5 of Series.) Price =50 cents=

=Concrete Monuments, Mausoleums and Burial Vaults.= By A. A. HOUGHTON.

The molding of concrete monuments to imitate the most expensive cut stone is explained in this treatise with working drawings of easily built molds. Cutting inscriptions and designs are also fully treated. (No. 6 of Series.) Price =50 cents=

=Molding Concrete Bathtubs, Aquariums and Natatoriums.= By A. A. HOUGHTON.

Simple molds and instruction are given for molding many styles of concrete bathtubs, swimming-pools, etc. These molds are easily built and permit rapid and successful work. (No. 7 of Series.) Price =50 cents=

=Concrete Bridges, Culverts and Sewers.= By A. A. HOUGHTON.

A number of ornamental concrete bridges with illustrations of molds are given. A collapsible center or core for bridges, culverts and sewers is fully illustrated with detailed instructions for building. (No. 8 of Series.) Price =50 cents=

=Constructing Concrete Porches.= By A. A. HOUGHTON.

A number of designs with working drawings of molds are fully explained so any one can easily construct different styles of ornamental concrete porches without the purchase of expensive molds. (No. 9 of Series.) Price =50 cents=

=Molding Concrete Flower-Pots, Boxes, Jardinieres, Etc.= By A. A. HOUGHTON.

The molds for producing many original designs of flower-pots, urns, flower-boxes, jardinieres, etc., are fully illustrated and explained, so the worker can easily construct and operate same. (No. 10 of Series.) Price =50 cents=

=Molding Concrete Fountains and Lawn Ornaments.= By A. A. HOUGHTON.

The molding of a number of designs of lawn seats, curbing, hitching posts, pergolas, sun dials and other forms of ornamental concrete for the ornamentation of lawns and gardens, is fully illustrated and described. (No. 11 of Series.) Price =50 cents=

=Concrete from Sand Molds.= By A. A. HOUGHTON.

A Practical Work treating on a process which has heretofore been held as a trade secret by the few who possessed it, and which will successfully mold every and any class of ornamental concrete work. The process of molding concrete with sand molds is of the utmost practical value, possessing the manifold advantages of a low cost of molds, the ease and rapidity of operation, perfect details to all ornamental designs, density and increased strength of the concrete, perfect curing of the work without attention and the easy removal of the molds regardless of any undercutting the design may have. 192 pages. Fully illustrated Price =$2.00=

=Ornamental Concrete without Molds.= By A. A. HOUGHTON.

The process for making ornamental concrete without molds has long been held as a secret, and now, for the first time, this process is given to the public. The book reveals the secret and is the only book published which explains a simple, practical method whereby the concrete worker is enabled, by employing wood and metal templates of different designs, to mold or model in concrete any Cornice, Archivolt, Column, Pedestal, Base Cap, Urn or Pier in a monolithic form--right upon the job. These may be molded in units or blocks and then built up to suit the specifications demanded. This work is fully illustrated, with detailed engravings. Price =$2.00=

=Concrete for the Farm and in the Shop.= By H. COLIN CAMPBELL, C.E., E.M.

"Concrete for the Farm and in the Shop" is a new book from cover to cover, illustrating and describing in plain, simple language many of the numerous applications of concrete within the range of the home worker. Among the subjects treated are: Principles of Reinforcing; Methods of Protecting Concrete so as to Insure Proper Hardening; Home-made Mixers; Mixing by Hand and Machine; Form Construction, Described and Illustrated by Drawings and Photographs; Construction of Concrete Walls and Fences; Concrete Fence Posts; Concrete Gate Posts; Corner Posts; Clothes Line Posts; Grape Arbor Posts; Tanks; Troughs; Cisterns; Hog Wallows; Feeding Floors and Barnyard Pavements; Foundations; Well Curbs and Platforms; Indoor Floors; Sidewalks; Steps; Concrete Hotbeds and Cold Frames; Concrete Slab Roofs; Walls for Buildings; Repairing Leaks in Tanks and Cisterns; and all topics associated with these subjects as bearing upon securing the best results from concrete are dwelt upon at sufficient length in plain every-day English so that the inexperienced person desiring to undertake a piece of concrete construction can, by following the directions set forth in this book, secure 100 per cent. success every time. A number of convenient and practical tables for estimating quantities, and some practical examples, are also given. (5x7.) 149 pages. 51 illustrations. Price =75 cents=

=Popular Handbook for Cement and Concrete Users.= By MYRON H. LEWIS.

This is a concise treatise of the principles and methods employed in the manufacture and use of cement in all classes of modern works. The author has brought together in this work all the salient matter of interest to the user of concrete and its many diversified products. The matter is presented in logical and systematic order, clearly written, fully illustrated and free from involved mathematics. Everything of value to the concrete user is given, including kinds of cement employed in construction, concrete architecture, inspection and testing, waterproofing, coloring and painting, rules, tables, working and cost data. The book comprises thirty-three chapters, as follow: Introductory. Kinds of Cement and How They are Made. Properties. Testing and Requirements of Hydraulic Cement. Concrete and Its Properties. Sand, Broken Stone and Gravel for Concrete. How to Proportion the Materials. How to Mix and Place Concrete. Forms of Concrete Construction. The Architectural and Artistic Possibilities of Concrete. Concrete Residences. Mortars, Plasters and Stucco, and How to Use Them. The Artistic Treatment of Concrete Surfaces. Concrete Building Blocks. The Making of Ornamental Concrete. Concrete Pipes, Fences, Posts, etc. Essential Features and Advantages of Reenforced Concrete. How to Design Reenforced Concrete Beams, Slabs and Columns. Explanations of the Methods and Principles in Designing Reenforced Concrete, Beams and Slabs. Systems of Reenforcement Employed. Reenforced Concrete in Factory and General Building Construction. Concrete in Foundation Work. Concrete Retaining Walls, Abutments and Bulkheads. Concrete Arches and Arch Bridges. Concrete Beam and Girder Bridges. Concrete in Sewerage and Draining Works. Concrete Tanks, Dams and Reservoirs. Concrete Sidewalks, Curbs and Pavements. Concrete in Railroad Construction. The Utility of Concrete on the Farm. The Waterproofing of Concrete Structures. Grout of Liquid Concrete and Its Use. Inspection of Concrete Work. Cost of Concrete Work. Some of the special features of the book are: 1.--The Attention Paid to the Artistic and Architectural Side of Concrete Work. 2.--The Authoritative Treatment of the Problem of Waterproofing Concrete. 3.--An Excellent Summary of the Rules to be Followed in Concrete Construction. 4.--The Valuable Cost Data and Useful Tables given. A valuable Addition to the Library of Every Cement and Concrete User. Price =$2.50=

WHAT IS SAID OF THIS BOOK:

"The field of Concrete Construction is well covered and the matter contained is well within the understanding of any person."--_Engineering-Contracting._

"Should be on the bookshelves of every contractor, engineer, and architect in the land."--_National Builder._

=Waterproofing Concrete.= By MYRON H. LEWIS.

Modern Methods of Waterproofing Concrete and Other Structures. A condensed statement of the Principles, Rules, and Precautions to be Observed in Waterproofing and Dampproofing Structures and Structural Materials. Paper binding. Illustrated. Price =50 cents=

~DICTIONARIES~

=Aviation Terms, Termes D'Aviation, English-French, French-English.= Compiled by Lieuts. VICTOR W. PAGÉ, A.S., S.C.U.S.R., and PAUL MONTARIOL, of the French Flying Corps, on duty on Signal Corps Aviation School, Mineola, L. I.

The lists contained are confined to essentials, and special folding plates are included to show all important airplane parts. The lists are divided in four sections as follows: 1.--Flying Field Terms. 2.--The Airplane. 3.--The Engine. 4.--Tools and Shop Terms.

A complete, well illustrated volume intended to facilitate conversation between English-speaking and French aviators. A very valuable book for all who are about to leave for duty overseas.

Approved for publication by Major W. G. Kilner, S.C., U.S.C.O. Signal Corps Aviation School, Hazelhurst Field, Mineola, L. I. This book should be in every Aviator's and Mechanic's Kit for ready reference. 128 pages, fully illustrated, with detailed engravings. Price =$1.00=

=Standard Electrical Dictionary.= By T. O'CONOR SLOANE.

An indispensable work to all interested in electrical science. Suitable alike for the student and professional. A practical handbook of reference containing definitions of about 5,000 distinct words, terms and phrases. The definitions are terse and concise; and include every term used in electrical science. Recently issued. An entirely new edition. Should be in the possession of all who desire to keep abreast with the progress of this branch of science. Complete, concise and convenient. 682 pages, 393 illustrations. Price =$3.00=

~DIES--METAL WORK~

=Dies: Their Construction and Use for the Modern Working of Sheet Metals.= By J. V. WOODWORTH.

A most useful book, and one which should be in the hands of all engaged in the press working of metals; treating on the Designing, Constructing, and Use of Tools, Fixtures and Devices, together with the manner in which they should be used in the Power Press, for the cheap and rapid production of the great variety of sheet-metal articles now in use. It is designed as a guide to the production of sheet-metal parts at the minimum of cost with the maximum of output. The hardening and tempering of Press tools and the classes of work which may be produced to the best advantage by the use of dies in the power press are fully treated. Its 515 illustrations show dies, press fixtures and sheet-metal working devices, the descriptions of which are so clear and practical that all metal-working mechanics will be able to understand how to design, construct and use them. Many of the dies and press fixtures treated were either constructed by the author or under his supervision. Others were built by skilful mechanics and are in use in large sheet-metal establishments and machine shops. 6th Revised and Enlarged Edition. Price =$3.00=

=Punches, Dies and Tools for Manufacturing in Presses.= By J. V. WOODWORTH.

This work is a companion volume to the author's elementary work entitled "Dies: Their Construction and Use." It does not go into the details of die-making to the extent of the author's previous book, but gives a comprehensive review of the field of operations carried on by presses. A large part of the information given has been drawn from the author's personal experience. It might well be termed an Encyclopedia of Die-Making, Punch-Making, Die-Sinking, Sheet-Metal Working, and Making of Special Tools, Sub-presses, Devices and Mechanical Combinations for Punching, Cutting, Bending, Forming, Piercing, Drawing, Compressing and Assembling Sheet-Metal Parts, and also Articles of other Materials in Machine Tools. 2d Edition. Price =$4.00=

=Drop Forging, Die-Sinking and Machine-Forming of Steel.= By J. V. WOODWORTH.

This is a practical treatise on Modern Shop Practice, Processes, Methods, Machine Tools, and Details treating on the Hot and Cold Machine-Forming of Steel and Iron into Finished Shapes: together with Tools, Dies, and Machinery involved in the manufacture of Duplicate Forgings and Interchangeable Hot and Cold Pressed Parts from Bar and Sheet Metal. This book fills a demand of long standing for information regarding drop-forgings, die-sinking and machine-forming of steel and the shop practice involved, as it actually exists in the modern drop-forging shop. The processes of die-sinking and force-making, which are thoroughly described and illustrated in this admirable work, are rarely to be found explained in such a clear and concise manner as is here set forth. The process of die-sinking relates to the engraving or sinking of the female or lower dies, such as are used for drop-forgings, hot and cold machine-forging, swedging, and the press working of metals. The process of force-making relates to the engraving or raising of the male or upper dies used in producing the lower dies for the press-forming and machine-forging of duplicate parts of metal.

In addition to the arts above mentioned the book contains explicit information regarding the drop-forging and hardening plants, designs, conditions, equipment, drop hammers, forging machines, etc., machine forging, hydraulic forging, autogenous welding and shop practice. The book contains eleven chapters, and the information contained in these chapters is just what will prove most valuable to the forged-metal worker. All operations described in the work are thoroughly illustrated by means of perspective half-tones and outline sketches of the machinery employed. 300 detailed illustrations. Price =$2.50=

~DRAWING--SKETCHING PAPER~

=Practical Perspective.= By RICHARDS and COLVIN.

Shows just how to make all kinds of mechanical drawings in the only practical perspective isometric. Makes everything plain, so that any mechanic can understand a sketch or drawing in this way. Saves time in the drawing room, and mistakes in the shops. Contains practical examples of various classes of work. 4th Edition. Price =50 cents=

=Linear Perspective Self-Taught.= By HERMAN T. C. KRAUS.

This work gives the theory and practice of linear perspective, as used in architectural, engineering and mechanical drawings. Persons taking up the study of the subject by themselves will be able, by the use of the instruction given, to readily grasp the subject, and by reasonable practice become good perspective draftsmen. The arrangement of the book is good; the plate is on the left-hand, while the descriptive text follows on the opposite page, so as to be readily referred to. The drawings are on sufficiently large scale to show the work clearly and are plainly figured. There is included a self-explanatory chart which gives all information necessary for the thorough understanding of perspective. This chart alone is worth many times over the price of the book. 2d Revised and Enlarged Edition. Price =$2.50=

=Self-Taught Mechanical Drawing and Elementary Machine Design.= By F. L. SYLVESTER, M.E., Draftsman, with additions by ERIK OBERG, associate editor of "Machinery."

This is a practical treatise on Mechanical Drawing and Machine Design, comprising the first principles of geometric and mechanical drawing, workshop mathematics, mechanics, strength of materials and the calculations and design of machine details. The author's aim has been to adapt this treatise to the requirements of the practical mechanic and young draftsman and to present the matter in as clear and concise a manner as possible. To meet the demands of this class of students, practically all the important elements of machine design have been dealt with, and in addition algebraic formulas have been explained, and the elements of trigonometry treated in the manner best suited to the needs of the practical man. The book is divided into 20 chapters, and in arranging the material, mechanical drawing, pure and simple, has been taken up first, as a thorough understanding of the principles of representing objects facilitates the further study of mechanical subjects. This is followed by the mathematics necessary for the solution of the problems in machine design which are presented later, and a practical introduction to theoretical mechanics and the strength of materials. The various elements entering into machine design, such as cams, gears, sprocket-wheels, cone pulleys, bolts, screws, couplings, clutches, shafting and fly-wheels, have been treated in such a way as to make possible the use of the work as a text-book for a continuous course of study. It is easily comprehended and assimilated even by students of limited previous training. 330 pages, 215 engravings. Price =$2.00=

=A New Sketching Paper.=

A new specially ruled paper to enable you to make sketches or drawings in isometric perspective without any figuring or fussing. It is being used for shop details as well as for assembly drawings, as it makes one sketch do the work of three, and no workman can help seeing just what is wanted.

Pads of 40 sheets, 6x9 inches. Price =25 cents= Pads of 40 sheets, 9x12 inches. Price =50 cents= 40 sheets, 12x18 inches. Price =$1.00=

~ELECTRICITY~

=Arithmetic of Electricity.= By Prof. T. O'CONOR SLOANE.

A practical treatise on electrical calculations of all kinds reduced to a series of rules, all of the simplest forms, and involving only ordinary arithmetic; each rule illustrated by one or more practical problems, with detailed solution of each one. This book is classed among the most useful works published on the science of electricity, covering as it does the mathematics of electricity in a manner that will attract the attention of those who are not familiar with algebraical formulas. 20th Edition. 160 pages. Price =$1.00=

=Commutator Construction.= By WM. BAXTER, JR.

The business end of any dynamo or motor of the direct current type is the commutator. This book goes into the designing, building, and maintenance of commutators, shows how to locate troubles and how to remedy them; everyone who fusses with dynamos needs this. 4th Edition. Price =25 cents=

=Dynamo Building for Amateurs, or How to Construct a Fifty-Watt Dynamo.= By ARTHUR J. WEED, Member of N. Y. Electrical Society.

A practical treatise showing in detail the construction of a small dynamo or motor, the entire machine work of which can be done on a small foot lathe. Dimensioned working drawings are given for each piece of machine work, and each operation is clearly described. This machine, when used as a dynamo, has an output of fifty watts; when used as a motor it will drive a small drill press or lathe. It can be used to drive a sewing machine on any and all ordinary work. The book is illustrated with more than sixty original engravings, showing the actual construction of the different parts. Among the contents are chapters on: 1. Fifty-Watt Dynamo. 2. Side Bearing Rods. 3. Field Punching. 4. Bearings. 5. Commutator. 6. Pulley. 7. Brush Holders. 8. Connection Board. 9. Armature Shaft. 10. Armature. 11. Armature Winding. 12. Field Winding. 13. Connecting and starting.

Paper. Price =50 Cents= Cloth. Price =$1.00=

=Electric Bells.= By M. B. SLEEPER.

A complete treatise for the practical worker in Installing, Operating and Testing Bell Circuits, Burglar Alarms, Thermostats, and other apparatus used with Electric Bells.

Both the electrician and the experimenter will find in this book new material which is essential in their work. Tools, bells, batteries, unusual circuits, burglar alarms, annunciator systems, thermostats, circuit breakers, time alarms, and other apparatus used in bell circuits are described from the standpoints of their application, construction and repair. The detailed instruction for building the apparatus will appeal to the experimenter particularly.

The practical worker will find the chapter on Wiring, Calculation of Wire Sizes and Magnet Winding, Upkeep of Systems, and the Location of Faults, of the greatest value in their work. Among the chapters are: Tools and Materials for Bell Work; How and Why Bell Work; Batteries for Small Installations; Making Bells and Push Buttons; Wiring Bell Systems; Construction of Annunciators and Signals; Burglary Alarms and Auxiliary Apparatus; More Elaborate Bell Systems; Finding Faults and Remedying Them. 124 pages, fully illustrated. Price =50 cents=

=Electric Lighting and Heating Pocket Book.= By SYDNEY F. WALKER.

This book puts in convenient form useful information regarding the apparatus which is likely to be attached to the mains of an electrical company. Tables of units and equivalents are included and useful electrical laws and formulas are stated. 438 pages, 300 engravings. Bound in leather. Pocket book form. Price =$3.00=

=Electric Wiring, Diagrams and Switchboards.= By NEWTON HARRISON, with additions by THOMAS POPPE.

A thoroughly practical treatise covering the subject of Electric Wiring in all its branches, deluding explanations and diagrams which are thoroughly explicit and greatly simplify the subject. Practical every-day problems in wiring are presented and the method of obtaining intelligent results clearly shown. Only arithmetic is used. Ohm's law is given a simple explanation with reference to wiring for direct and alternating currents. The fundamental principle of drop of potential in circuits is shown with its various applications. The simple circuit is developed with the position of mains, feeders and branches; their treatment as a part of a wiring plan and their employment in house wiring clearly illustrated. Some simple facts about testing are included in connection with the wiring. Molding and conduit work are given careful consideration; and switchboards are systematically treated, built up and illustrated, showing the purpose they serve, for connection with the circuits, and to shunt and compound wound machines. The simple principles of switchboard construction, the development of the switchboard, the connections of the various instruments, including the lightning arrester, are also plainly set forth.

Alternating current wiring is treated, with explanations of the power factor, conditions calling for various sizes of wire, and a simple way of obtaining the sizes for single-phase, two-phase and three-phase circuits. This is the only complete work issued showing and telling you what you should know about direct and alternating current wiring. It is a ready reference. The work is free from advanced technicalities and mathematics, arithmetic being used throughout. It is in every respect a handy, well-written, instructive, comprehensive volume on wiring for the wireman, foreman, contractor, or electrician. 2nd Revised Edition. 303 pages, 130 illustrations. Price =$1.50=

=Electric Furnaces and their Industrial Applications.= By J. WRIGHT.

This is a book which will prove of interest to many classes of people: the manufacturer who desires to know what product can be manufactured successfully in the electric furnace, the chemist who wishes to post himself on the electro-chemistry, and the student of science who merely looks into the subject from curiosity. New, Revised and Enlarged Edition. 320 pages. Fully illustrated, cloth. Price =$3.00=

=Electric Toy Making, Dynamo Building, and Electric Motor Construction.= By Prof. T. O'CONOR SLOANE.

This work treats of the making at home of electrical toys, electrical apparatus, motors, dynamos, and instruments in general, and is designed to bring within the reach of young and old the manufacture of genuine and useful electrical appliances. The work is especially designed for amateurs and young folks.

Thousands of our young people are daily experimenting, and busily engaged in making electrical toys and apparatus of various kinds. The present work is just what is wanted to give the much needed information in a plain, practical manner, with illustrations to make easy the carrying out of the work. 20th Edition. Price =$1.00=

=Practical Electricity.= By Prof. T. O'CONOR SLOANE.

This work of 768 pages was previously known as Sloane's Electricians' Hand Book, and is intended for the practical electrician who has to make things go. The entire field of electricity is covered within its pages. Among some of the subjects treated are: The Theory of the Electric Current and Circuit, Electro-Chemistry, Primary Batteries, Storage Batteries, Generation and Utilization of Electric Powers, Alternating Current, Armature Winding, Dynamos and Motors, Motor Generators, Operation of the Central Station Switchboards, Safety Appliances, Distribution of Electric Light and Power, Street Mains, Transformers, Arc and Incandescent Lighting, Electric Measurements, Photometry, Electric Railways, Telephony, Bell-Wiring, Electric-Plating, Electric Heating, Wireless Telegraphy, etc. It contains no useless theory; everything is to the point. It teaches you just what you want to know about electricity. It is the standard work published on the subject. Forty-one chapters, 556 engravings. Price =$2.50=

=Electricity Simplified.= By Prof. T. O'CONOR SLOANE.

The object of "Electricity Simplified" is to make the subject as plain as possible and to show what the modern conception of electricity is; to show how two plates of different metal, immersed in acid, can send a message around the globe; to explain how a bundle of copper wire rotated by a steam engine can be the agent in lighting our streets; to tell what the volt, ohm and ampere are, and what high and low tension mean; and to answer the questions that perpetually arise in the mind in this age of electricity. 13th Edition. 172 pages. Illustrated. Price =$1.00=

=House Wiring.= By THOMAS W. POPPE.

This work describes and illustrates the actual installation of Electric Light Wiring, the manner in which the work should be done, and the method of doing it. The book can be conveniently carried in the pocket. It is intended for the Electrician, Helper and Apprentice. It solves all Wiring Problems and contains nothing that conflicts with the rulings of the National Board of Fire Underwriters. It gives just the information essential to the Successful Wiring of a Building. Among the subjects treated are: Locating the Meter. Panel-Boards. Switches. Plug Receptacles. Brackets. Ceiling Fixtures. The Meter Connections. The Feed Wires. The Steel Armored Cable System. The Flexible Steel Conduit System. The Ridig Conduit System. A digest of the National Board of Fire Underwriters' rules relating to metallic wiring systems. Various switching arrangements explained and diagrammed. The easiest method of testing the Three- and Four-way circuits explained. The grounding of all metallic wiring systems and the reason for doing so shown and explained. The insulation of the metal parts of lamp fixtures and the reason for the same described and illustrated. 125 pages. 2nd Edition, revised and enlarged. Fully illustrated. Flexible cloth. Price =50 cents=

=How to Become a Successful Electrician.= By Prof. T. O'CONOR SLOANE.

Every young man who wishes to become a successful electrician should read this book. It tells in simple language the surest and easiest way to become a successful electrician. The studies to be followed, methods of work, field of operation and the requirements of the successful electrician are pointed out and fully explained. Every young engineer will find this an excellent stepping stone to more advanced works on electricity which he must master before success can be attained. Many young men become discouraged at the very outstart by attempting to read and study books that are far beyond their comprehension. This book serves as the connecting link between the rudiments taught in the public schools and the real study of electricity. It is interesting from cover to cover. 18th Revised Edition, just issued. 205 pages. Illustrated. Price =$1.00=

=Management of Dynamos.= By LUMMIS-PATERSON.

A handbook of theory and practice. This work is arranged in three parts. The first part covers the elementary theory of the dynamo. The second part, the construction and action of the different classes of dynamos in common use are described; while the third part relates to such matters as affect the practical management and working of dynamos and motors. 4th Edition. 292 pages, 117 illustrations. Price =$1.50=

=Standard Electrical Dictionary.= By T. O'CONOR SLOANE.

An indispensable work to all interested in electrical science. Suitable alike for the student and professional. A practical handbook of reference containing definitions of about 5,000 distinct words, terms and phrases. The definitions are terse and concise and include every term used in electrical science. Recently issued. An entirely new edition. Should be in the possession of all who desire to keep abreast with the progress of this branch of science. In its arrangement and typography the book is very convenient. The word or term defined is printed in black-faced type, which readily catches the eye, while the body of the page is in smaller but distinct type. The definitions are well worded, and so as to be understood by the non-technical reader. The general plan seems to be to give an exact, concise definition, and then amplify and explain in a more popular way. Synonyms are also given, and references to other words and phrases are made. A very complete and accurate index of fifty pages is at the end of the volume; and as this index contains all synonyms, and as all phrases are indexed in every reasonable combination of words, reference to the proper place in the body of the book is readily made. It is difficult to decide how far a book of this character is to keep the dictionary form, and to what extent it may assume the encyclopedia form. For some purposes, concise, exactly worded definitions are needed; for other purposes, more extended descriptions are required. This book seeks to satisfy both demands, and does it with considerable success. 682 pages, 393 illustrations. 12th Edition. Price =$3.00=

=Storage Batteries Simplified.= By VICTOR W. PAGÉ, M.E.

A complete treatise on storage battery operating principles, repairs and applications. The greatly increasing application of storage batteries in modern engineering and mechanical work has created a demand for a book that will consider this subject completely and exclusively. This is the most thorough and authoritative treatise ever published on this subject. It is written in easily understandable, non-technical language so that any one may grasp the basic principles of storage battery action as well as their practical industrial applications. All electric and gasoline automobiles use storage batteries. Every automobile repairman, dealer or salesman should have a good knowledge of maintenance and repair of these important elements of the motor car mechanism. This book not only tells how to charge, care for and rebuild storage batteries but also outlines all the industrial uses. Learn how they run street cars, locomotives and factory trucks. Get an understanding of the important functions they perform in submarine boats, isolated lighting plants, railway switch and signal systems, marine applications, etc. This book tells how they are used in central station standby service, for starting automobile motors and in ignition systems. Every practical use of the modern storage battery is outlined in this treatise. 320 pages, fully illustrated. Price =$1.50=

=Switchboards.= By WILLIAM BAXTER, JR.

This book appeals to every engineer and electrician who wants to know the practical side of things. It takes up all sorts and conditions of dynamos, connections and circuits, and shows by diagram and illustration just how the switchboard should be connected. Includes direct and alternating current boards, also those for arc lighting, incandescent and power circuits. Special treatment on high voltage boards for power transmission. 2nd Edition. 190 pages, Illustrated. Price =$1.50=

=Telephone Construction, Installation, Wiring, Operation and Maintenance.= By W. H. RADCLIFFE and H. C. CUSHING.

This book is intended for the amateur, the wireman, or the engineer who desires to establish a means of telephonic communication between the rooms of his home, office, or shop. It deals only with such things as may be of use to him rather than with theories.

Gives the principles of construction and operation of both the Bell and Independent instruments; approved methods of installing and wiring them; the means of protecting them from lightning and abnormal currents; their connection together for operation as series or bridging stations; and rules for their inspection and maintenance. Line wiring and the wiring and operation of special telephone systems are also treated. Intricate mathematics are avoided, and all apparatus, circuits and systems are thoroughly described. The appendix contains definitions of units and terms used in the text. Selected wiring tables, which are very helpful, are also included. Among the subjects treated are Construction, Operation, and Installation of Telephone Instruments; Inspection and Maintenance of Telephone Instruments; Telephone Line Wiring; Testing Telephone Line Wires and Cables; Wiring and Operation of Special Telephone Systems, etc. 2nd Edition, Revised and Enlarged. 223 pages, 154 illustrations. Price =$1.00=

=Wireless Telegraphy and Telephony Simply Explained.= By ALFRED P. MORGAN.

This is undoubtedly one of the most complete and comprehensible treatises on the subject ever published, and a close study of its pages will enable one to master all the details of the wireless transmission of messages. The author has filled a long-felt want and has succeeded in furnishing a lucid, comprehensible explanation in simple language of the theory and practice of wireless telegraphy and telephony.

Among the contents are: Introductory; Wireless Transmission and Reception--The Aerial System, Earth Connections--The Transmitting Apparatus, Spark Coils and Transformers, Condensers, Helixes, Spark Gaps, Anchor Gaps, Aerial Switches--The Receiving Apparatus, Detectors, etc.--Tuning and Coupling, Tuning Coils, Loose Couplers, Variable Condensers, Directive Wave Systems--Miscellaneous Apparatus, Telephone Receivers, Range of Stations, Static Interference--Wireless Telephones, Sound and Sound Waves, The Vocal Cords and Ear--Wireless Telephone, How Sounds Are Changed into Electric Waves--Wireless Telephones, The Apparatus--Summary. 154 pages, 156 engravings. Price =$1.00=

=Wiring a House.= By HERBERT PRATT.

Shows a house already built; tells just how to start about wiring it; where to begin; what wire to use; how to run it according to Insurance Rules; in fact, just the information you need. Directions apply equally to a shop. 4th Edition. Price =25 cents=

~FACTORY MANAGEMENT, ETC.~

=Modern Machine Shop Construction, Equipment and Management.= By O. E. PERRIGO, M.E.

The only work published that describes the modern machine shop or manufacturing plant from the time the grass is growing on the site intended for it until the finished product is shipped. By a careful study of its thirty-two chapters the practical man may economically build, efficiently equip, and successfully manage the modern machine shop or manufacturing establishment. Just the book needed by those contemplating the erection of modern shop buildings, the rebuilding and reorganization of old ones, or the introduction of modern shop methods, time and cost systems. It is a book written and illustrated by a practical shop man for practical shop men who are too busy to read _theories_ and want _facts_. It is the most complete all-around book of its kind ever published. It is a practical book for practical men, from the apprentice in the shop to the president in the office. It minutely describes and illustrates the most simple and yet the most efficient time and cost system yet devised. 2nd Revised and Enlarged Edition, just issued. 384 pages, 219 illustrations. Price =$5.00=

~FUEL~

=Combustion of Coal and the Prevention of Smoke.= By WM. M. BARR.

This book has been prepared with special reference to the generation of heat by the combustion of the common fuels found in the United States, and deals particularly with the conditions necessary to the economic and smokeless combustion of bituminous coals in Stationary and Locomotive Steam Boilers.

The presentation of this important subject is systematic and progressive. The arrangement of the book is in a series of practical questions to which are appended accurate answers, which describe in language, free from technicalities, the several processes involved in the furnace combustion of American fuels; it clearly states the essential requisites for perfect combustion, and points out the best methods for furnace construction for obtaining the greatest quantity of heat from any given quality of coal. Nearly 350 pages, fully illustrated. Price =$1.00=

=Smoke Prevention and Fuel Economy.= By BOOTH and KERSHAW.

A complete treatise for all interested in smoke prevention and combustion, being based on the German work of Ernst Schmatolla, but it is more than a mere translation of the German treatise, much being added. The authors show as briefly as possible the principles of fuel combustion, the methods which have been and are at present in use, as well as the proper scientific methods for obtaining all the energy in the coal and burning it without smoke. Considerable space is also given to the examination of the waste gases, and several of the representative English and American mechanical stoker and similar appliances are described. The losses carried away in the waste gases are thoroughly analyzed and discussed in the Appendix, and abstracts are also here given of various patents on combustion apparatus. The book is complete and contains much of value to all who have charge of large plants. 194 pages. Illustrated. Price =$2.50=

~GAS ENGINES AND GAS~

=Gas, Gasoline and Oil Engines.= By GARDNER D. HISCOX. Revised by VICTOR W. PAGÉ, M.E.

Just issued New 1918 Edition, Revised and Enlarged. Every user of a gas engine needs this book. Simple, instructive and right up-to-date. The only complete work on the subject. Tells all about internal combustion engineering, treating exhaustively on the design, construction and practical application of all forms of gas, gasoline, kerosene and crude petroleum-oil engines. Describes minutely all auxiliary systems, such as lubrication, carburetion and ignition. Considers the theory and management of all forms of explosive motors for stationary and marine work, automobiles, aeroplanes and motor-cycles. Includes also Producer Gas and Its Production. Invaluable instructions for all students, gas-engine owners, gas-engineers, patent experts, designers, mechanics, draftsmen and all having to do with the modern power. Illustrated by over 400 engravings, many specially made from engineering drawings, all in correct proportion. 650 pages, 435 engravings. Price =$2.50 net=

=The Gasoline Engine on the Farm: Its Operation, Repair and Uses.= By XENO W. PUTNAM.

This is a practical treatise on the Gasoline and Kerosene Engine intended for the man who wants to know just how to manage his engine and how to apply it to all kinds of farm work to the best advantage.

This book abounds with hints and helps for the farm and suggestions for the home and house-wife. There is so much of value in this book that it is impossible to adequately describe it in such small space. Suffice to say that it is the kind of a book every farmer will appreciate and every farm home ought to have. Includes selecting the most suitable engine for farm work, its most convenient and efficient installation, with chapters on troubles, their remedies, and how to avoid them. The care and management of the farm tractor in plowing, harrowing, harvesting and road grading are fully covered; also plain directions are given for handling the tractor on the road. Special attention is given to relieving farm life of its drudgery by applying power to the disagreeable small tasks which must otherwise be done by hand. Many home made contrivances for cutting wood, supplying kitchen, garden, and barn with water, loading, hauling and unloading hay, delivering grain to the bins or the feed trough are included; also full directions for making the engine milk the cows, churn, wash, sweep the house and clean the windows, etc. Very fully illustrated with drawings of working parts and cuts showing Stationary, Portable and Tractor Engines doing all kinds of farm work. All money-making farms utilize power. Learn how to utilize power by reading the pages of this book. It is an aid to the result getter, invaluable to the up-to-date farmer, student, blacksmith, implement dealer and, in fact, all who can apply practical knowledge of stationary gasoline engines or gas tractors to advantage. 530 pages. Nearly 180 engravings. Price =$2.00=

WHAT IS SAID OF THIS BOOK:

"Am much pleased with the book and find it to be very complete and up-to-date. I will heartily recommend it to students and farmers whom I think would stand in need of such a work, as I think it is an exceptionally good one."--_N. S. Gardiner_, Prof. in Charge, Clemson Agr. College of S. C.; Dept. of Agri. and Agri. Exp. Station, Clemson College, S. C.

"I feel that Mr. Putnam's book covers the main points which a farmer should know."--_R. T. Burdick_, Instructor in Agronomy, University of Vermont, Burlington, Vt.

=Gasoline Engines: Their Operation, Use and Care.= By A. HYATT VERRILL.

The simplest, latest and most comprehensive popular work published on Gasoline Engines, describing what the Gasoline Engine is; its construction and operation; how to install it; how to select it; how to use it and how to remedy troubles encountered. Intended for Owners, Operators and Users of Gasoline Motors of all kinds. This work fully describes and illustrates the various types of Gasoline Engines used in Motor Boats, Motor Vehicles and Stationary Work. The parts, accessories and appliances are described with chapters on ignition, fuel, lubrication, operation and engine troubles. Special attention is given to the care, operation and repair of motors, with useful hints and suggestions on emergency repairs and makeshifts. A complete glossary of technical terms and an alphabetically arranged table of troubles and their symptoms form most valuable and unique features of this manual. Nearly every illustration in the book is original, having been made by the author. Every page is full of interest and value. A book which you cannot afford to be without. 275 pages, 152 specially made engravings. Price =$1.50=

=Gas Engine Construction, or How to Build a Half-horsepower Gas Engine.= By PARSELL and WEED.

A practical treatise of 300 pages describing the theory and principles of the action of Gas Engines of various types and the design and construction of a half-horsepower Gas Engine, with illustrations of the work in actual progress, together with the dimensioned working drawings, giving clearly the sizes of the various details; for the student, the scientific investigator, and the amateur mechanic. This book treats of the subject more from the standpoint of practice than that of theory. The principles of operation of Gas Engines are clearly and simply described, and then the actual construction of a half-horsepower engine is taken up, step by step, showing in detail the making of the Gas Engine. 3rd Edition. 300 pages. Price =$2.50=

=How to Run and Install Two- and Four-Cycle Marine Gasoline Engines.= By C. VON CULIN.

Revised and enlarged edition just issued. The object of this little book is to furnish a pocket instructor for the beginner, the busy man who uses an engine for pleasure or profit, but who does not have the time or inclination for a technical book, but simply to thoroughly understand how to properly operate, install and care for his own engine. The index refers to each trouble, remedy, and subject alphabetically. Being a quick reference to find the cause, remedy and prevention for troubles, and to become an expert with his own engine. Pocket size. Paper binding. Price =25 cents=

=Modern Gas Engines and Producer Gas Plants.= By R. E. MATHOT.

A guide for the gas engine designer, user, and engineer in the construction, selection, purchase, installation, operation, and maintenance of gas engines. More than one book on gas engines has been written, but not one has thus far even encroached on the field covered by this book. Above all, Mr. Mathot's work is a practical guide. Recognizing the need of a volume that would assist the gas engine user in understanding thoroughly the motor upon which he depends for power, the author has discussed his subject without the help of any mathematics and without elaborate theoretical explanations. Every part of the gas engine is described in detail, tersely, clearly, with a thorough understanding of the requirements of the mechanic. Helpful suggestions as to the purchase of an engine, its installation, care, and operation, form a most valuable feature of the work. 320 pages, 175 detailed illustrations. Price =$2.50=

=The Modern Gas Tractor.= By VICTOR W. PAGÉ, M. E.

A complete treatise describing all types and sizes of gasoline, kerosene and oil tractors. Considers design and construction exhaustively, gives complete instructions for care, operation and repair, outlines all practical applications on the road and in the field. The best and latest work on farm tractors and tractor power plants. A work needed by farmers, students, blacksmiths, mechanics, salesmen, implement dealers, designers and engineers. 2nd Edition, Revised. 504 pages, 228 illustrations, 3 folding plates. Price =$2.00=

~GEARING AND CAMS~

=Bevel Gear Tables.= By D. AG. ENGSTROM.

A book that will at once commend itself to mechanics and draftsmen. Does away with all the trigonometry and fancy figuring on bevel gears, and makes it easy for anyone to lay them out or make them just right. There are 36 full-page tables that show every necessary dimension for all sizes or combinations you're apt to need. No puzzling, figuring or guessing. Gives placing distance, all the angles (including cutting angles), and the correct cutter to use. A copy of this prepares you for anything in the bevel-gear line. 3rd Edition. 66 pages. Price =$1.00=

=Change Gear Devices.= By OSCAR E. PERRIGO.

A practical book for every designer, draftsman, and mechanic interested in the invention and development of the devices for feed changes on the different machines requiring such mechanism. All the necessary information on this subject is taken up, analyzed, classified, sifted, and concentrated for the use of busy men who have not the time to go through the masses of irrelevant matter with which such a subject is usually encumbered and select such information as will be useful to them.

It shows just what has been done, how it has been done, when it was done, and who did it. It saves time in hunting up patent records and re-inventing old ideas. 88 pages. 3rd Edition. Price =$1.00=

=Drafting of Cams.= By LOUIS ROUILLION.

The laying out of cams is a serious problem unless you know how to go at it right. This puts you on the right road for practically any kind of cam you are likely to run up against. 3rd Edition. Price =25 Cents=

~HYDRAULICS~

=Hydraulic Engineering.= By GARDNER D. HISCOX.

A treatise on the properties, power, and resources of water for all purposes. Including the measurement of streams, the flow of water in pipes or conduits; the horsepower of falling water, turbine and impact water-wheels, wave motors, centrifugal, reciprocating and air-lift pumps. With 300 figures and diagrams and 36 practical tables. All who are interested in water-works development will find this book a useful one, because it is an entirely practical treatise upon a subject of present importance and cannot fail in having a far-reaching influence, and for this reason should have a place in the working library of every engineer. Among the subjects treated are: Historical Hydraulics; Properties of Water; Measurement of the Flow of Streams; Flow from Sub-surface Orifices and Nozzles; Flow of Water in Pipes; Siphons of Various Kinds; Dams and Great Storage Reservoirs; City and Town Water Supply; Wells and Their Reinforcement; Air-lift Methods of Raising Water; Artesian Wells; Irrigation of Arid Districts; Water Power; Water Wheels; Pumps and Pumping Machinery; Reciprocating Pumps; Hydraulic Power Transmission; Hydraulic Mining; Canals; Ditches; Conduits and Pipe Lines; Marine Hydraulics; Tidal and Sea Wave Power, etc. 320 pages. Price =$4.00=

~ICE AND REFRIGERATION~

=Pocketbook of Refrigeration and Ice Making.= By A. J. WALLIS-TAYLOR.

This is one of the latest and most comprehensive reference books published on the subject of refrigeration and cold storage. It explains the properties and refrigerating effect of the different fluids in use, the management of refrigerating machinery and the construction and insulation of cold rooms with their required pipe surface for different degrees of cold; freezing mixtures and non-freezing brines, temperatures of cold rooms for all kinds of provisions, cold storage charges for all classes of goods, ice making and storage of ice, data and memoranda for constant reference by refrigerating engineers, with nearly one hundred tables containing valuable references to every fact and condition required in the installment and operation of a refrigerating plant. New edition just published. Price =$1.50=

~INVENTIONS--PATENTS~

=Inventors' Manual: How to Make a Patent Pay.=

This is a book designed as a guide to inventors in perfecting their inventions, taking out their patents and disposing of them. It is not in any sense a Patent Solicitor's Circular nor a Patent Broker's Advertisement. No advertisements of any description appear in the work. It is a book containing a quarter of a century's experience of a successful inventor, together with notes based upon the experience of many other inventors.

Among the subjects treated in this work are: How to Invent. How to Secure a Good Patent. Value of Good Invention. How to Exhibit an Invention. How to Interest Capital. How to Estimate the Value of a Patent. Value of Design Patents. Value of Foreign Patents. Value of Small Inventions. Advice on Selling Patents. Advice on the Formation of Stock Companies. Advice on the Formation of Limited Liability Companies. Advice on Disposing of Old Patents. Advice as to Patent Attorneys. Advice as to Selling Agents. Forms of Assignments. License and Contracts. State Laws Concerning Patent Rights. 1900 Census of the United States by Counts of Over 10,000 Population. Revised Edition. 120 pages. Price =$1.00=

~KNOTS~

=Knots, Splices and Rope Work.= By A. HYATT VERRILL.

This is a practical book giving complete and simple directions for making all the most useful and ornamental knots in common use, with chapters on Splicing, Pointing, Seizing, Serving, etc. This book is fully illustrated with 154 original engravings, which show how each knot, tie or splice is formed, and its appearance when finished. The book will be found of the greatest value to Campers, Yachtsmen, Travelers, Boy Scouts, in fact, to anyone having occasion to use or handle rope or knots for any purpose. The book is thoroughly reliable and practical, and is not only a guide, but a teacher. It is the standard work on the subject. Among the contents are: 1. Cordage, Kinds of Rope. Construction of Rope, Parts of Rope Cable and Bolt Rope. Strength of Rope, Weight of Rope. 2. Simple Knots and Bends. Terms Used in Handling Rope. Seizing Rope. 3. Ties and Hitches. 4. Noose, Loops and Mooring Knots. 5. Shortenings, Grommets and Salvages. 6. Lashings, Seizings and Splices. 7. Fancy Knots and Rope Work. 128 pages, 150 original engravings. 2nd Revised Edition. Price =75 cents=

~LATHE WORK~

=Lathe Design, Construction, and Operation, with Practical Examples of Lathe Work.= By OSCAR E. PERRIGO.

A new, revised edition, and the only complete American work on the subject, written by a man who knows not only how work ought to be done, but who also knows how to do it, and how to convey this knowledge to others. It is strictly up-to-date in its descriptions and illustrations. Lathe history and the relations of the lathe to manufacturing are given; also a description of the various devices for feeds and thread-cutting mechanisms from early efforts in this direction to the present time. Lathe design is thoroughly discussed, including back gearing, driving cones, thread-cutting gears, and all the essential elements of the modern lathe. The classification of lathes is taken up, giving the essential differences of the several types of lathes including, as is usually understood, engine lathes, bench lathes, speed lathes, forge lathes, gap lathes, pulley lathes, forming lathes, multiple-spindle lathes, rapid-reduction lathes, precision lathes, turret lathes, special lathes, electrically driven lathes, etc. In addition to the complete exposition on construction and design, much practical matter on lathe installation, care and operation has been incorporated in the enlarged new edition. All kinds of lathe attachments for drilling, milling, etc., are described and complete instructions are given to enable the novice machinist to grasp the art of lathe operation as well as the principles involved in design. A number of difficult machining operations are described at length and illustrated. The new edition has nearly 500 pages and 350 illustrations. Price =$2.50=

WHAT IS SAID OF THIS BOOK:

"This is a lathe book from beginning to end, and is just the kind of a book which one delights to consult--a masterly treatment of the subject in hand."--_Engineering News._

"This work will be of exceptional interest to any one who is interested in lathe practice, as one very seldom sees such a complete treatise on a subject as this is on the lathe."--_Canadian Machinery._

=Practical Metal Turning.= By JOSEPH G. HORNER.

A work of 404 pages, fully illustrated, covering in a comprehensive manner the modern practice of machining metal parts in the lathe, including the regular engine lathe, its essential design, its uses, its tools, its attachments, and the manner of holding the work and performing the operations. The modernized engine lathe, its methods, tools and great range of accurate work. The turret lathe, its tools, accessories and methods of performing its functions. Chapters on special work, grinding, tool holders, speeds, feeds, modern tool steels, etc. Second edition =$3.50=

=Turning and Boring Tapers.= By FRED H. COLVIN.

There are two ways to turn tapers; the right way and one other. This treatise has to do with the right way; it tells you how to start the work properly, how to set the lathe, what tools to use and how to use them, and forty and one other little things that you should know. Fourth edition =25 cents=

~LIQUID AIR~

=Liquid Air and the Liquefaction of Gases.= By T. O'CONOR SLOANE.

This book gives the history of the theory, discovery and manufacture of Liquid Air, and contains an illustrated description of all the experiments that have excited the wonder of audiences all over the country. It shows how liquid air, like water, is carried hundreds of miles and is handled in open buckets. It tells what may be expected from it in the near future.

A book that renders simple one of the most perplexing chemical problems of the century. Startling developments illustrated by actual experiments.

It is not only a work of scientific interest and authority, but is intended for the general reader, being written in a popular style--easily understood by every one. Second edition. 365 pages. Price =$2.00=

~LOCOMOTIVE ENGINEERING~

=Air-Brake Catechism.= By ROBERT H. BLACKALL.

This book is a standard text-book. It covers the Westinghouse Air-Brake Equipment, including the No. 5 and the No. 6 E.-T. Locomotive Brake Equipment; the K (Quick Service) Triple Valve for Freight Service; and the Cross-Compound Pump. The operation of all parts of the apparatus is explained in detail, and a practical way of finding their peculiarities and defects, with a proper remedy, is given. It contains 2,000 questions with their answers, which will enable any railroad man to pass any examination on the subject of Air Brakes. Endorsed and used by air-brake instructors and examiners on nearly every railroad in the United States. Twenty-sixth edition. 411 pages, fully illustrated with colored plates and diagrams. Price =$2.00=

=American Compound Locomotives.= By FRED H. COLVIN.

The only book on compounds for the engineman or shopman that shows in a plain, practical way the various features of compound locomotives in use. Shows how they are made, what to do when they break down or balk. Contains sections as follows: A Bit of History. Theory of Compounding Steam Cylinders. Baldwin Two-Cylinder Compound. Pittsburg Two-Cylinder Compound. Rhode Island Compound. Richmond Compound. Rogers Compound. Schenectady Two-Cylinder Compound. Vauclain Compound. Tandem Compounds. Baldwin Tandem. The Colvin-Wightman Tandem. Schenectady Tandem. Balanced Locomotives. Baldwin Balanced Compound. Plans for Balancing. Locating Blows. Breakdowns. Reducing Valves. Drifting. Valve Motion. Disconnecting. Power of Compound Locomotives. Practical Notes.

Fully illustrated and containing ten special "Duotone" inserts on heavy Plate Paper, showing different types of Compounds. 142 pages. Price =$1.00=

=Application of Highly Superheated Steam to Locomotives.= By ROBERT GARBE.

A practical book which cannot be recommended too highly to those motive-power men who are anxious to maintain the highest efficiency in their locomotives. Contains special chapters on Generation of Highly Superheated Steam; Superheated Steam and the Two-Cylinder Simple Engine; Compounding and Superheating; Designs of Locomotive Superheaters; Constructive Details of Locomotives Using Highly Superheated Steam. Experimental and Working Results. Illustrated with folding plates and tables. Cloth. Price =$2.50=

=Combustion of Coal and the Prevention of Smoke.= By WM. M. BARR.

This book has been prepared with special reference to the generation of heat by the combustion of the common fuels found in the United States and deals particularly with the conditions necessary to the economic and smokeless combustion of bituminous coal in Stationary and Locomotive Steam Boilers.

Presentation of this important subject is systematic and progressive. The arrangement of the book is in a series of practical questions to which are appended accurate answers, which describe in language free from technicalities the several processes involved in the furnace combustion of American fuels; it clearly states the essential requisites for perfect combustion, and points out the best methods of furnace construction for obtaining the greatest quantity of heat from any given quality of coal. Nearly 350 pages, fully illustrated. Price =$1.00=

=Diary of a Round-House Foreman.= By T. S. REILLY.

This is the greatest book of railroad experiences ever published. Containing a fund of information and suggestions along the line of handling men, organizing, etc., that one cannot afford to miss. 176 pages. Price =$1.00=

=Link Motions, Valves and Valve Setting.= By FRED H. COLVIN, Associate Editor of "American Machinist."

A handy book for the engineer or machinist that clears up the mysteries of valve setting. Shows the different valve gears in use, how they work, and why. Piston and slide valves of different types are illustrated and explained. A book that every railroad man in the motive-power department ought to have. Contains chapters on Locomotive Link Motion, Valve Movements, Setting Slide Valves, Analysis by Diagrams, Modern Practice, Slip of Block, Slice Valves, Piston Valves, Setting Piston Valves, Joy-Allen Valve Gear, Walschaert Valve Gear, Gooch Valve Gear, Alfree-Hubbell Valve Gear, etc., etc. Fully illustrated. Price =50 cents=

=Locomotive Boiler Construction.= By FRANK A. KLEINHANS.

The construction of boilers in general is treated and, following this, the locomotive boiler is taken up in the order in which its various parts go through the shop. Shows all types of boilers used; gives details of construction; practical facts, such as life of riveting, punches and dies; work done per day, allowance for bending and flanging sheets and other data. Including the recent Locomotive Boiler Inspection Laws and Examination Questions with their answers for Government Inspectors. Contains chapters on Laying-Out Work; Flanging and Forging; Punching; Shearing; Plate Planing; General Tables; Finishing Parts; Bending; Machinery Parts; Riveting; Boiler Details; Smoke-Box Details; Assembling and Calking; Boiler-Shop Machinery, etc., etc.

There isn't a man who has anything to do with boiler work, either new or repair work, who doesn't need this book. The manufacturer, superintendent, foreman and boiler worker--all need it. No matter what the type of boiler, you'll find a mint of information that you wouldn't be without. Over 400 pages, five large folding plates. Price =$3.00=

=Locomotive Breakdowns and their Remedies.= By GEO. L. FOWLER. Revised by WM. W. WOOD, Air-Brake Instructor. Just issued. Revised pocket edition.

It is out of the question to try and tell you about every subject that is covered in this pocket edition of Locomotive Breakdowns. Just imagine all the common troubles that an engineer may expect to happen some time, and then add all of the unexpected ones, troubles that could occur, but that you have never thought about, and you will find that they are all treated with the very best methods of repair. Walschaert Locomotive Valve Gear Troubles, Electric Headlight Troubles, as well as Questions and Answers on the Air Brake are all included. 312 pages. 8th Revised Edition. Fully illustrated. Price =$1.00=

=Locomotive Catechism.= By ROBERT GRIMSHAW.

The revised edition of "Locomotive Catechism," by Robert Grimshaw, is a New Book from Cover to Cover. It contains twice as many pages and double the number of illustrations of previous editions. Includes the greatest amount of practical information ever published on the construction and management of modern locomotives. Specially Prepared Chapters on the Walschaert Locomotive Valve Gear, the Air-Brake Equipment and the Electric Headlight are given.

It commends itself at once to every Engineer and Fireman, and to all who are going in for examination or promotion. In plain language, with full, complete answers, not only all the questions asked by the examining engineer are given, but those which the young and less experienced would ask the veteran, and which old hands ask as "stickers." It is a veritable Encyclopedia of the Locomotive, is entirely free from mathematics, easily understood and thoroughly up to date. Contains over 4,000 Examination Questions with their Answers. 825 pages, 437 illustrations, and 3 folding plates. 28th Revised Edition. Price =$2.50=

=Practical Instructor and Reference Book for Locomotive Firemen and Engineers.= By CHAS. F. LOCKHART.

An entirely new book on the Locomotive. It appeals to every railroad man, as it tells him how things are done and the right way to do them. Written by a man who has had years of practical experience in locomotive shops and on the road firing and running. The information given in this book cannot be found in any other similar treatise. Eight hundred and fifty-one questions with their answers are included, which will prove specially helpful to those preparing for examination. Practical information on: The Construction and Operation of Locomotives, Breakdowns and their Remedies, Air Brakes and Valve Gears. Rules and Signals are handled in a thorough manner. As a book of reference it cannot be excelled. The book is divided into six parts, as follows: 1. The Fireman's Duties. 2. General Description of the Locomotive. 3. Breakdowns and their Remedies. 4. Air Brakes. 5. Extracts from Standard Rules. 6. Questions for Examination. The 851 questions have been carefully selected and arranged. These cover the examinations required by the different railroads. 368 pages, 88 illustrations. Price =$1.50=

=Prevention of Railroad Accidents, or Safety in Railroading.= By GEORGE BRADSHAW.

This book is a heart-to-heart talk with Railroad Employees, dealing with facts, not theories, and showing the men in the ranks, from every-day experience, how accidents occur and how they may be avoided. The book is illustrated with seventy original photographs and drawings showing the safe and unsafe methods of work. No visionary schemes, no ideal pictures. Just Plain Facts and Practical Suggestions are given. Every railroad employee who reads the book is a better and safer man to have in railroad service. It gives just the information which will be the means of preventing many injuries and deaths. All railroad employees should procure a copy, read it, and do their part in preventing accidents. 169 pages. Pocket size. Fully illustrated. Price =50 cents=

=Train Rule Examinations Made Easy.= By G. E. COLLINGWOOD.

This is the only practical work on train rules in print. Every detail is covered, and puzzling points are explained in simple, comprehensive language, making it a practical treatise for the Train Dispatcher, Engineman, Trainman, and all others who have to do with the movements of trains. Contains complete and reliable information of the Standard Code of Train Rules for single track. Shows Signals in Colors, as used on the different roads. Explains fully the practical application of train orders, giving a clear and definite understanding of all orders which may be used. The meaning and necessity for certain rules are explained in such a manner that the student may know beyond a doubt the rights conferred under any orders he may receive or the action required by certain rules. As nearly all roads require trainmen to pass regular examinations, a complete set of examination questions, with their answers, are included. These will enable the student to pass the required examinations with credit to himself and the road for which he works. 2nd Edition, Revised. 256 pages, fully illustrated, with Train Signals in Colors. Price =$1.25=

=The Walschaert and Other Modern Radial Valve Gears for Locomotives.= By WM. W. WOOD.

If you would thoroughly understand the Walschaert Valve Gear you should possess a copy of this book, as the author takes the plainest form of a steam engine--a stationary engine in the rough, that will only turn its crank in one direction--and from it builds up, with the reader's help, a modern locomotive equipped with the Walschaert Valve Gear, complete. The points discussed are clearly illustrated: Two large folding plates that show the positions of the valves of both inside or outside admission type, as well as the links and other parts of the gear when the crank is at nine different points in its revolution, are especially valuable in making the movement clear. These employ sliding cardboard models which are contained in a pocket in the cover.

The book is divided into five general divisions, as follows: 1. Analysis of the gear. 2. Designing and erecting the gear. 3. Advantages of the gear. 4. Questions and answers relating to the Walschaert Valve Gear. 5. Setting valves with the Walschaert Valve Gear; the three primary types of locomotive valve motion; modern radial valve gears other than the Walschaert; the Hobart All-free Valve and Valve Gear, with questions and answers on breakdowns; the Baker-Pilliod Valve Gear; the Improved Baker-Pilliod Valve Gear, with questions and answers on breakdowns.

The questions with full answers given will be especially valuable to firemen and engineers in preparing for an examination for promotion. 245 pages. 3rd Revised Edition. Price =$1.50=

=Westinghouse E-T Air-Brake Instruction Pocket Book.= By WM. W. WOOD, Air-Brake Instructor.

Here is a book for the railroad man, and the man who aims to be one. It is without doubt the only complete work published on the Westinghouse E-T Locomotive Brake Equipment. Written by an Air-Brake Instructor who knows just what is needed. It covers the subject thoroughly. Everything about the New Westinghouse Engine and Tender Brake Equipment, including the standard No. 5 and the Perfected No. 6 style of brake, is treated in detail. Written in plain English and profusely illustrated with Colored Plates, which enable one to trace the flow of pressures throughout the entire equipment. The best book ever published on the Air Brake. Equally good for the beginner and the advanced engineer. Will pass any one through any examination. It informs and enlightens you on every point. Indispensable to every engineman and trainman.

Contains examination questions and answers on the E-T equipment. Covering what the E-T Brake is. How it should be operated. What to do when defective. Not a question can be asked of the engineman up for promotion, on either the No. 5 or the No. 6 E-T equipment, that is not asked and answered in the book. If you want to thoroughly understand the E-T equipment get a copy of this book. It covers every detail. Makes Air-Brake troubles and examinations easy. Price =$1.50=

~MACHINE-SHOP PRACTICE~

=American Tool Making and Interchangeable Manufacturing.= By J. V. WOODWORTH.

A "shoppy" book, containing no theorizing, no problematical or experimental devices. There are no badly proportioned and impossible diagrams, no catalogue cuts, but a valuable collection of drawings and descriptions of devices, the rich fruits of the author's own experience. In its 500-odd pages the one subject only, Tool Making, and whatever relates thereto, is dealt with. The work stands without a rival. It is a complete, practical treatise, on the art of American Tool Making and system of interchangeable manufacturing as carried on to-day in the United States. In it are described and illustrated all of the different types and classes of small tools, fixtures, devices, and special appliances which are in general use in all machine-manufacturing and metal-working establishments where economy, capacity, and interchangeability in the production of machined metal parts are imperative. The science of jig making is exhaustively discussed, and particular attention is paid to drill jigs, boring, profiling and milling fixtures and other devices in which the parts to be machined are located and fastened within the contrivances. All of the tools, fixtures, and devices illustrated and described have been or are used for the actual production of work, such as parts of drill presses, lathes, patented machinery, typewriters, electrical apparatus, mechanical appliances, brass goods, composition parts, mould products, sheet-metal articles, drop-forgings, jewelry, watches, medals, coins, etc. 531 pages. Price =$4.00=

=HENLEY'S ENCYCLOPEDIA OF PRACTICAL ENGINEERING AND ALLIED TRADES.= EDITED by JOSEPH G. HORNER, A.M.I., M.E.

This set of five volumes contains about 2,500 pages with thousands of illustrations, including diagrammatic and sectional drawings with full explanatory details. This work covers the entire practice of Civil and Mechanical Engineering. The best known experts in all branches of engineering have contributed to these volumes. The Cyclopedia is admirably well adapted to the needs of the beginner and the self-taught practical man, as well as the mechanical engineer, designer, draftsman, shop superintendent, foreman, and machinist. The work will be found a means of advancement to any progressive man. It is encyclopedic in scope, thorough and practical in its treatment on technical subjects, simple and clear in its descriptive matter, and without unnecessary technicalities or formulæ. The articles are as brief as may be and yet give a reasonably clear and explicit statement of the subject, and are written by men who have had ample practical experience in the matters of which they write. It tells you all you want to know about engineering and tells it so simply, so clearly, so concisely, that one cannot help but understand. As a work of reference it is without a peer. Complete set of five volumes, price =$25.00=

=The Modern Machinist.= By JOHN T. USHER.

This is a book, showing by plain description and by profuse engravings made expressly for the work, all that is best, most advanced, and of the highest efficiency in modern machine-shop practice, tools and implements, showing the way by which and through which, as Mr. Maxim says "American machinists have become and are the finest mechanics in the world." Indicating as it does, in every line, the familiarity of the author with every detail of daily experience in the shop, it cannot fail to be of service to any man practically connected with the shaping or finishing of metals.

There is nothing experimental or visionary about the book, all devices being in actual use and giving good results. It might be called a compendium of shop methods, showing a variety of special tools and appliances which will give new ideas to many mechanics, from the superintendent down to the man at the bench. It will be found a valuable addition to any machinist's library, and should be consulted whenever a new or difficult job is to be done, whether it is boring, milling, turning, or planing, as they are all treated m a practical manner. Fifth edition. 320 pages. 250 illustrations. Price =$2.50=

=THE WHOLE FIELD OF MECHANICAL MOVEMENTS COVERED BY MR. HISCOX'S TWO BOOKS=

_We publish two books by Gardner D. Hiscox that will keep you from "inventing" things that have been done before, and suggest ways of doing things that you have not thought of before. Many a man spends time and money pondering over some mechanical problem, only to learn, after he has solved the problem, that the same thing has been accomplished and put in practice by others long before. Time and money spent in an effort to accomplish what has already been accomplished are time and money LOST. The whole field of mechanics, every known mechanical movement, and practically every device are covered by these two books. If the thing you want has been invented, it is illustrated in them. If it hasn't been invented, then you'll find in them the nearest things to what you want, some movements or devices that will apply in your case, perhaps; or which will give you a key from which to work. No book or set of books ever published is of more real value to the Inventor, Draftsman, or practical Mechanic than the two volumes described below._

=Mechanical Movements, Powers, and Devices.= By GARDNER D. HISCOX.

This is a collection of 1,890 engravings of different mechanical motions and appliances, accompanied by appropriate text, making it a book of great value to the inventor, the draftsman, and to all readers with mechanical tastes. The book is divided into eighteen sections or chapters, in which the subject-matter is classified under the following heads: Mechanical Powers; Transmission of Power; Measurement of Power; Steam Power; Air Power Appliances; Electric Power and Construction; Navigation and Roads; Gearing; Motion and Devices; Controlling Motion; Horological; Mining; Mill and Factory Appliances; Construction and Devices; Drafting Devices; Miscellaneous Devices, etc. 15th Edition. 400 octavo pages. Price =$3.00=

=Mechanical Appliances, Mechanical Movements and Novelties of Construction.= By GARDNER D. HISCOX.

This is a supplementary volume to the one upon mechanical movements. Unlike the first volume, which is more elementary in character, this volume contains illustrations and descriptions of many combinations of motions and of mechanical devices and appliances found in different lines of machinery, each device being shown by a line drawing with a description showing its working parts and the method of operation. From the multitude of devices described and illustrated might be mentioned, in passing, such items as conveyors and elevators, Pony brakes, thermometers, various types of boilers, solar engines, oil-fuel burners, condensers, evaporators, Corliss and other valve gears, governors, gas engines, water motors of various descriptions, air ships, motors and dynamos, automobile and motor bicycles, railway lock signals, car couplers, link and gear motions, ball bearings, breech-block mechanism for heavy guns, and a large accumulation of others of equal importance. One thousand specially made engravings. 396 octavo pages. Fourth edition. Price =$3.00=

=Machine-Shop Tools and Shop Practice.= By W. H. VANDERVOORT.

A work of 555 pages and 673 illustrations, describing in every detail the construction, operation and manipulation of both hand and machine tools. Includes chapters on filing, fitting and scraping surfaces; on drills, reamers, taps and dies; the lathe and its tools: planers, shapers, and their tools; milling machines and cutters; gear cutters and gear cutting; drilling machines and drill work; grinding machines and their work; hardening and tempering; gearing, belting and transmission machinery; useful data and tables. Sixth edition. Price =$3.00=

=Machine-Shop Arithmetic.= By COLVIN-CHENEY.

This is an arithmetic of the things you have to do with daily. It tells you plainly about: how to find areas in figures; how to find surface or volume of balls or spheres; handy ways for calculating; about compound gearing; cutting screw threads on any lathe; drilling for taps; speeds of drills; taps, emery wheels, grindstones, milling cutters, etc.; all about the Metric system with conversion tables; properties of metals; strength of bolts and nuts; decimal equivalent of an inch. All sorts of machine-shop figuring and 1,001 other things, any one of which ought to be worth more than the price of this book to you, as it saves you the trouble of bothering the boss. 6th Edition. 131 pages. Price =50 cents=

=Modern Machine-Shop Construction, Equipment and Management.= By OSCAR E. PERRIGO.

The only work published that describes the Modern Shop or Manufacturing Plant from the time the grass is growing on the site intended for it until the finished product is shipped. Just the book needed by those contemplating the erection of modern shop buildings, the rebuilding and reorganization of old ones, or the introduction of Modern Shop Methods, time and cost systems. It is a book written and illustrated by a practical shop man for practical shop men who are too busy to read theories and want facts. It is the most complete all-round book of its kind ever published. Second Edition, Revised. 384 large quarto pages. 219 original and specially made illustrations. 2nd Revised and Enlarged Edition. Price =$5.00=

=Modern Milling Machines: Their Design, Construction, and Operation.= By JOSEPH G. HORNER.

This book describes and illustrates the Milling Machine and its work in such a plain, clear and forceful manner, and illustrates the subject so clearly and completely, that the up-to-date machinist, student or mechanical engineer cannot afford to do without the valuable information which it contains. It describes not only the early machines of this class, but notes their gradual development into the splendid machines of the present day, giving the design and construction of the various types, forms, and special features produced by prominent manufacturers, American and foreign. 304 pages, 300 illustrations. Cloth. Price =$4.00=

="Shop Kinks."= By ROBERT GRIMSHAW.

A book of 400 pages and 222 illustrations, being entirely different from any other book on machine-shop practice. Departing from conventional style, the author avoids universal or common shop usage and limits his work to showing special ways of doing things better, more cheaply and more rapidly than usual. As a result the advanced methods of representative establishments of the world are placed at the disposal of the reader. This book shows the proprietor where large savings are possible, and how products may be improved. To the employee it holds out suggestions that, properly applied, will hasten his advancement. No shop can afford to be without it. It bristles with valuable wrinkles and helpful suggestions. It will benefit all, from apprentice to proprietor. Every machinist, at any age, should study its pages. Fifth edition. Price =$2.50=

=Threads and Thread Cutting.= By COLVIN and STABEL.

This clears up many of the mysteries of thread-cutting, such as double and triple threads, internal threads, catching threads, use of hobs, etc. Contains a lot of useful hints and several tables. Third edition. Price =25 cents=

~MANUAL TRAINING~

=Economics of Manual Training.= By LOUIS ROUILLION.

The only book published that gives just the information needed by all interested in Manual Training, regarding Buildings, Equipment, and Supplies. Shows exactly what is needed for all grades of the work from the Kindergarten to the High and Normal School. Gives itemized lists of everything used in Manual Training Work and tells just what it ought to cost. Also shows where to buy supplies, etc. Contains 174 pages, and is fully illustrated. Second edition. Price =$1.50=

~MARINE ENGINEERING~

=The Naval Architect's and Shipbuilder's Pocket Book of Formulæ, Rules, and Tables and Marine Engineer's and Surveyor's Handy Book of Reference.= By CLEMENT MACKROW and LLOYD WOOLLARD.

The eleventh Revised and Enlarged Edition of this most comprehensive work has just been issued. It is absolutely indispensable to all engaged in the Shipbuilding Industry, as it condenses into a compact form all data and formulæ that are ordinarily required. The book is completely up to date, including among other subjects a section on Aeronautics. 750 pages, limp leather binding. Price =$5.00 net=

=Marine Engines and Boilers: Their Design and Construction.= By DR. G. BAUER, LESLIE S. ROBERTSON and S. BRYAN DONKIN.

In the words of Dr. Bauer, the present work owes its origin to an oft felt want of a condensed treatise embodying the theoretical and practical rules used in designing marine engines and boilers. The need of such a work has been felt by most engineers engaged in the construction and working of marine engines, not only by the younger men, but also by those of greater experience. The fact that the original German work was written by the chief engineer of the famous Vulcan Works, Stettin, is in itself a guarantee that this book is in all respects thoroughly up-to-date, and that it embodies all the information which is necessary for the design and construction of the highest types of marine engines and boilers. It may be said that the motive power which Dr. Bauer has placed in the fast German liners that have been turned out of late years from the Stettin Works represent the very best practice in marine engineering of the present day. The work is clearly written, thoroughly systematic, theoretically sound; while the character of the plans, drawings, tables, and statistics is without reproach. The illustrations are careful reproductions from actual working drawings, with some well-executed photographic views of completed engines and boilers. 744 pages, 550 illustrations and numerous tables. Cloth. Price =$9.00 net=

~MINING~

=Ore Deposits, with a Chapter on Hints to Prospectors.= By J. P. JOHNSON.

This book gives a condensed account of the ore deposits at present known in South Africa. It is also intended as a guide to the prospector. Only an elementary knowledge of geology and some mining experience are necessary in order to understand this work. With these qualifications, it will materially assist one in his search for metalliferous mineral occurrences and, so far as simple ores are concerned, should enable one to form some idea of the possibilities of any he may find. Illustrated. Cloth. Price =$2.00=

=Practical Coal Mining.= By T. H. COCKIN.

An important work, containing 428 pages and 213 illustrations, complete with practical details, which will intuitively impart to the reader not only a general knowledge of the principles of coal mining, but also considerable insight into allied subjects. The treatise is positively up-to-date in every instance, and should be in the hands of every colliery engineer, geologist, mine operator, superintendent, foreman, and all others who are interested in or connected with the industry. 3d Edition. Cloth. Price =$2.50=

=Physics and Chemistry of Mining.= By T. H. BYROM.

A practical work for the use of all preparing for examinations in mining or qualifying for colliery managers' certificates. The aim of the author in this excellent book is to place clearly before the reader useful and authoritative data which will render him valuable assistance in his studies. The only work of its kind published. The information incorporated in it will prove of the greatest practical utility to students, mining engineers, colliery managers, and all others who are specially interested in the present-day treatment of mining problems. 160 pages, illustrated. Price =$2.00=

~PATTERN MAKING~

=Practical Pattern Making.= By F. W. BARROWS.

This book, now in its second edition, is a comprehensive and entirely practical treatise on the subject of pattern making, illustrating pattern work in both wood and metal, and with definite instructions on the use of plaster of paris in the trade. It gives specific and detailed descriptions of the materials used by pattern makers, and describes the tools, both those for the bench and the more interesting machine tools, having complete chapters on the Lathe, the Circular Saw, and the Band Saw. It gives many examples of pattern work, each one fully illustrated and explained with much detail. These examples, in their great variety, offer much that will be found of interest to all pattern makers, and especially to the younger ones, who are seeking information on the more advanced branches of their trade.

In this second edition of the work will be found much that is new, even to those who have long practised this exacting trade. In the description of patterns as adapted to the Moulding Machine many difficulties which have long prevented the rapid and economical production of castings are overcome; and this great, new branch of the trade is given much space. Stripping plate and stool plate work and the less expensive vibrator, or rapping plate work, are all explained in detail.

Plain, every-day rules for lessening the cost of patterns, with a complete system of cost keeping, a detailed method of marking, applicable to all branches of the trade, with complete information showing what the pattern is, its specific title, its cost, date of production, material of which it is made, the number of pieces and core-boxes, and its location in the pattern safe, all condensed into a most complete card record, with cross index. The book closes with an original and practical method for the inventory and valuation of patterns. Containing nearly 350 pages and 170 illustrations. Price =$2.00=

~PERFUMERY~

=Perfumes and Cosmetics: Their Preparation and Manufacture.= By G. W. ASKINSON, Perfumer.

A comprehensive treatise, in which there has been nothing omitted that could be of value to the perfumer or manufacturer of toilet preparations. Complete directions for making handkerchief perfumes, smelling-salts, sachets, fumigating pastilles; preparations for the care of the skin, the mouth, the hair, cosmetics, hair dyes and other toilet articles are given, also a detailed description of aromatic substances; their nature, tests of purity, and wholesome manufacture, including a chapter on synthetic products, with formulas for their use. A book of general as well as professional interest, meeting the wants not only of the druggist and perfume manufacturer, but also of the general public. Among the contents are: 1. The History of Perfumery. 2. About Aromatic Substances in General. 3. Odors from the Vegetable Kingdom. 4. The Aromatic Vegetable Substances Employed in Perfumery. 5. The Animal Substances Used in Perfumery. 6. The Chemical Products Used in Perfumery. 7. The Extraction of Odors. 8. The Special Characteristics of Aromatic Substances. 9 The Adulteration of Essential Oils and Their Recognition. 10. Synthetic Products. 11. Table of Physical Properties of Aromatic Chemicals. 12. The Essences or Extracts Employed in Perfumery. 13. Directions for Making the Most Important Essences and Extracts. 14. The Division of Perfumery. 15. The Manufacture of Handkerchief Perfumes. 16. Formulas for Handkerchief Perfumes. 17. Ammoniacal and Acid Perfumes. 18. Dry Perfumes. 19. Formulas for Dry Perfumes. 20. The Perfumes Used for Fumigation. 21. Antiseptic and Therapeutic Value of Perfumes. 22. Classification of Odors. 23. Some Special Perfumery Products. 24. Hygiene and Cosmetic Perfumery. 25. Preparations for the Care of the Skin. 26. Manufacture of Casein. 27. Formulas for Emulsions. 28. Formulas for Cream. 29. Formulas for Meals, Pastes and Vegetable Milk. 30. Preparations Used for the Hair. 31. Formulas for Hair Tonics and Restorers. 32. Pomades and Hair Oils 33. Formulas for the Manufacture of Pomades and Hair Oils. 34. Hair Dyes and Depilatories. 35. Wax Pomades, Bandolines and Brilliantines. 36. Skin Cosmetics and Face Lotions. 37. Preparations for the Nails. 38. Water Softeners and Bath Salts. 39. Preparations for the Care of the Mouth. 40. The Colors Used in Perfumery. 41. The Utensils Used in the Toilet. Fourth edition, much enlarged and brought up to date. Nearly 400 pages, illustrated. Price =$5.00=

WHAT IS SAID OF THIS BOOK:

"The most satisfactory work on the subject of Perfumery that we have ever seen."

"We feel safe in saying that here is a book on Perfumery that will not disappoint you, for it has practical and excellent formulæ that are within your ability to prepare readily."

"We recommend the volume as worthy of confidence, and say that no purchaser will be disappointed in securing from its pages good value for its cost, and a large dividend on the same, even if he should use but one per cent. of its working formulæ. There is money in it for every user of its information."--_Pharmaceutical Record._

~PLUMBING~

=Mechanical Drawing for Plumbers.= By R. M. STARBUCK.

A concise, comprehensive and practical treatise on the subject of mechanical drawing in its various modern applications to the work of all who are in any way connected with the plumbing trade. Nothing will so help the plumber in estimating and in explaining work to customers and workmen as a knowledge of drawing, and to the workman it is of inestimable value if he is to rise above his position to positions of greater responsibility. Among the chapters contained are: 1. Value to plumber of knowledge of drawing; tools required and their use; common views needed in mechanical drawing. 2. Perspective versus mechanical drawing in showing plumbing construction. 3. Correct and incorrect methods in plumbing drawing; plan and elevation explained. 4. Floor and cellar plans and elevation; scale drawings; use of triangles. 5. Use of triangles; drawing of fittings, traps, etc. 6. Drawing plumbing elevations and fittings. 7. Instructions in drawing plumbing elevations. 8. The drawing of plumbing fixtures; scale drawings. 9. Drawings of fixtures and fittings. 10. Inking of drawings. 11. Shading of drawings. 12. Shading of drawings. 13. Sectional drawings; drawing of threads. 14. Plumbing elevations from architect's plan. 15. Elevations of separate parts of the plumbing system. 16. Elevations from the architect's plans. 17. Drawings of detail plumbing connections. 18. Architect's plans and plumbing elevations of residence. 19. Plumbing elevations of residence (_continued_); plumbing plans for cottage. 20. Plumbing elevations; roof connections. 21. Plans and plumbing elevations for six-flat building. 22. Drawing of various parts of the plumbing system; use of scales. 23. Use of architect's scales. 24. Special features in the illustrations of country plumbing. 25. Drawing of wrought-iron piping, valves, radiators, coils, etc. 26. Drawing of piping to illustrate heating systems. 150 illustrations. Price =$1.50=

=Modern Plumbing Illustrated.= By R. M. STARBUCK.

This book represents the highest standard of plumbing work. It has been adopted and used as a reference book by the United States Government in its sanitary work in Cuba, Porto Rico and the Philippines, and by the principal Boards of Health of the United States and Canada.

It gives connections, sizes and working data for all fixtures and groups of fixtures. It is helpful to the master plumber in demonstrating to his customers and in figuring work. It gives the mechanic and student quick and easy access to the best modern plumbing practice. Suggestions for estimating plumbing construction are contained in its pages. This book represents, in a word, the latest and best up-to-date practice and should be in the hands of every architect, sanitary engineer and plumber who wishes to keep himself up to the minute on this important feature of construction. Contains following chapters, each illustrated with a full-page plate: Kitchen sink, laundry tubs, vegetable wash sink; lavatories, pantry sinks, contents of marble slabs; bath tub, foot and sitz bath, shower bath; water closets, venting of water closets; low-down water closets, water closets operated by flush valves, water closet range; slop sink, urinals, the bidet; hotel and restaurant sink, grease trap; refrigerators, safe wastes, laundry waste, lines of refrigerators, bar sinks, soda fountain sinks; horse stall, frost-proof water closets; connections for S traps, venting; connections for drum traps; soil-pipe connections; supporting of soil pipe; main trap and fresh-air inlet: floor drains and cellar drains, subsoil drainage; water closets and floor connections; local venting; connections for bath rooms; connections for bath rooms, _continued_; examples of poor practice; roughing work ready for test; testing of plumbing systems; method of continuous venting; continuous venting for two-floor work; continuous venting for two lines of fixtures on three or more floors; continuous venting of water closets; plumbing for cottage house; construction for cellar piping; plumbing for residence, use of special fittings; plumbing for two-flat house: plumbing for apartment building, plumbing for double apartment building; plumbing for office building; plumbing for public toilet rooms; plumbing for public toilet rooms, _continued_; plumbing for bath establishment; plumbing for engine house, factory plumbing, automatic flushing for schools, factories, etc.; use of flushing valves; urinals for public toilet rooms; the Durham system, the destruction of pipes by electrolysis; construction of work without use of lead; automatic sewage lift; automatic sump tank; country plumbing; construction of cesspools; septic tank and automatic sewage siphon; water supply for country house; thawing of water mains and service by electricity; double boilers; hot water supply of large buildings; automatic control of hot-water tank; suggestions for estimating plumbing construction. 407 octavo pages, fully illustrated by 57 full-page engravings. Third, revised and enlarged edition, just issued. Price =$4.00=

=Standard Practical Plumbing.= By R. M. STARBUCK.

A complete practical treatise of 450 pages, covering the subject of Modern Plumbing in all its branches, a large amount of space being devoted to a very complete and practical treatment of the subject of Hot Water Supply and Circulation and Range Boiler Work. Its thirty chapters include about every phase of the subject one can think of, making it an indispensable work to the master plumber, the journeyman plumber, and the apprentice plumber, containing chapters on: the plumber's tools; wiping solder; composition and use; joint wiping; lead work; traps; siphonage of traps; venting; continuous venting; house sewer and sewer connections; house drain; soil piping, roughing; main trap and fresh air inlet; floor, yard, cellar drains, rain leaders, etc.; fixture wastes; water closets; ventilation; improved plumbing connections; residence plumbing; plumbing for hotels, schools, factories, stables, etc.; modern country plumbing; filtration of sewage and water supply; hot and cold supply; range boilers; circulation; circulating pipes; range boiler problems; hot water for large buildings; water lift and its use; multiple connections for hot water boilers; heating of radiation by supply system; theory for the plumber; drawing for the plumber. Fully illustrated by 347 engravings. Price =$3.00=

~RECIPE BOOK~

=Henley's Twentieth Century Book of Recipes, Formulas and Processes.= Edited by GARDNER D. HISCOX.

The most valuable Techno-chemical Formula Book published, including over 10,000 selected scientific, chemical, technological, and practical recipes and processes.

This is the most complete Book of Formulas ever published, giving thousands of recipes for the manufacture of valuable articles for everyday use. Hints, Helps, Practical Ideas, and Secret Processes are revealed within its pages. It covers every branch of the useful arts and tells thousands of ways of making money, and is just the book everyone should have at his command.

Modern in its treatment of every subject that properly falls within its scope, the book may truthfully be said to present the very latest formulas to be found in the arts and industries, and to retain those processes which long experience has proven worthy of a permanent record. To present here even a limited number of the subjects which find a place in this valuable work would be difficult. Suffice to say that in its pages will be found matter of intense interest and immeasurably practical value to the scientific amateur and to him who wishes to obtain a knowledge of the many processes used in the arts, trades and manufacture, a knowledge which will render his pursuits more instructive and remunerative. Serving as a reference book to the small and large manufacturer and supplying intelligent seekers with the information necessary to conduct a process, the work will be found of inestimable worth to the Metallurgist, the Photographer, the Perfumer, the Painter, the Manufacturer of Glues, Pastes, Cements, and Mucilages, the Compounder of Alloys, the Cook, the Physician, the Druggist, the Electrician, the Brewer, the Engineer, the Foundryman, the Machinist, the Potter, the Tanner, the Confectioner, the Chiropodist, the Manicurist, the Manufacturer of Chemical Novelties and Toilet Preparations, the Dyer, the Electroplater, the Enameler, the Hat Maker, the Ink Manufacturer, the Optician, the Farmer, the Dairyman, the Paper Maker, the Wood and Metal Worker, the Chandler and Soap Maker, the Veterinary Surgeon, and the Technologist in general.

A mine of information, and up-to-date in every respect. A book which will prove of value to EVERYONE, as it covers every branch of the Useful Arts. Every home needs this book; every office, every factory, every store, every public and private enterprise--EVERYWHERE--should have a copy. 800 pages. Price =$3.00=

WHAT IS SAID OF THIS BOOK:

"Your Twentieth Century Book of Recipes, Formulas, and Processes duly received. I am glad to have a copy of it, and if I could not replace it, money couldn't buy it. It is the best thing of the sort I ever saw." (Signed) M. E. TRUX, Sparta, Wis.

"There are few persons who would not be able to find in the book some single formula that would repay several times the cost of the book."--_Merchants' Record and Show Window._

"I purchased your book, 'Henley's Twentieth Century Book of Recipes, Formulas and Processes,' about a year ago and it is worth its weight in _gold_."--WM. H. MURRAY, Bennington, Vt.

"ONE OF THE WORLD'S MOST USEFUL BOOKS"

"Some time ago I got one of your 'Twentieth Century Books of Formulas,' and have made my living from it ever since. I am alone since my husband's death with two small children to care for and am trying so hard to support them. I have customers who take from me Toilet Articles I put up, following directions given in the book, and I have found everyone of them to be fine."--MRS. J. H. MCMAKEN, West Toledo, Ohio.

~RUBBER~

=Rubber Hand Stamps and the Manipulation of India Rubber.= BY T. O'CONOR SLOANE.

This book gives full details on all points, treating in a concise and simple manner the elements of nearly everything it is necessary to understand for a commencement in any branch of the India Rubber Manufacture. The making of all kinds of Rubber Hand Stamps, Small Articles of India Rubber, U. S. Government Composition, Dating Hand Stamps, the Manipulation of Sheet Rubber, Toy Balloons, India Rubber Solutions, Cements, Blackings, Renovating, Varnish, and Treatment for India Rubber Shoes, etc.; the Hektograph Stamp Inks, and Miscellaneous Notes, with a Short Account of the Discovery, Collection and Manufacture of India Rubber, are set forth in a manner designed to be readily understood, the explanations being plain and simple. Including a chapter on Rubber Tire Making and Vulcanizing; also a chapter on the uses of rubber in Surgery and Dentistry. 3rd Revised and Enlarged Edition. 175 pages. Illustrated =$1.00=

~SAWS~

=Saw Filing and Management of Saws.= By ROBERT GRIMSHAW.

A practical hand-book on filing, gumming, swaging, hammering, and the brazing of band saws, the speed, work, and power to run circular saws, etc. A handy book for those who have charge of saws, or for those mechanics who do their own filing, as it deals with the proper shape and pitches of saw teeth of all kinds and gives many useful hints and rules for gumming, setting, and filing, and is a practical aid to those who use saws for any purpose. Complete tables of proper shape, pitch, and saw teeth as well as sizes and number of teeth of various saws are included. 3rd Edition, Revised and Enlarged. Illustrated. Price =$1.00=

~STEAM ENGINEERING~

=American Stationary Engineering.= By W. E. CRANE.

This book begins at the boiler room and takes in the whole power plant. A plain talk on every-day work about engines, boilers, and their accessories. It is not intended to be scientific or mathematical. All formulas are in simple form so that any one understanding plain arithmetic can readily understand any of them. The author has made this the most practical book in print; has given the results of his years of experience, and has included about all that has to do with an engine room or a power plant. You are not left to guess at a single point. You are shown clearly what to expect under the various conditions; how to secure the best results; ways of preventing "shut downs" and repairs; in short, all that goes to make up the requirements of a good engineer, capable of taking charge of a plant. It's plain enough for practical men and yet of value to those high in the profession.

A partial list of contents is: The boiler room, cleaning boilers, firing, feeding; pumps, inspection and repair; chimneys, sizes and cost; piping; mason work; foundations; testing cement; pile driving; engines, slow and high speed; valves; valve setting; Corliss engines, setting valves, single and double eccentric; air pumps and condensers; different types of condensers; water needed; lining up; pounds; pins not square in crosshead or crank; engineers' tools; pistons and piston rings; bearing metal; hardened copper; drip pipes from cylinder jacket; belts, how made, care of; oils; greases; testing lubricants; rules and tables, including steam tables; areas of segments; squares and square roots; cubes and cube root; areas and circumferences of circles. Notes on: Brick work; explosions; pumps; pump valves; heaters, economizers; safety valves; lap, lead, and clearance. Has a complete examination for a license, etc., etc. 3rd Edition. 345 pages, illustrated. Price =$2.00=

=Engine Runner's Catechism.= By ROBERT GRIMSHAW.

A practical treatise for the stationary engineer, telling how to erect, adjust, and run the principal steam engines in use in the United States. Describing the principal features of various special and well-known makes of engines: Temper Cut-off, Shipping and Receiving Foundations, Erecting and Starting, Valve Setting, Care and Use, Emergencies, Erecting and Adjusting Special Engines.

The questions asked throughout the catechism are plain and to the point, and the answers are given in such simple language as to be readily understood by anyone. All the instructions given are complete and up-to-date; and they are written in a popular style, without any technicalities or mathematical formulæ. The work is of a handy size for the pocket, clearly and well printed, nicely bound, and profusely illustrated.

To young engineers this catechism will be of great value, especially to those who may be preparing to go forward to be examined for certificates of competency; and to engineers generally it will be of no little service, as they will find in this volume more really practical and useful information than is to be found anywhere else within a like compass. 387 pages. 7th Edition. Price =$2.00=

=Modern Steam Engineering in Theory and Practice.= By GARDNER D. HISCOX.

This is a complete and practical work issued for Stationary Engineers and Firemen, dealing with the care and management of boilers, engines, pumps, superheated steam, refrigerating machinery, dynamos, motors, elevators, air compressors, and all other branches with which the modern engineer must be familiar. Nearly 200 questions with their answers on steam and electrical engineering, likely to be asked by the Examining Board, are included.

Among the chapters are: Historical: steam and its properties; appliances for the generation of steam; types of boilers; chimney and its work; heat economy of the feed water; steam pumps and their work; incrustation and its work; steam above atmospheric pressure; flow of steam from nozzles; superheated steam and its work; adiabatic expansion of steam; indicator and its work; steam engine proportions; slide valve engines and valve motion; Corliss engine and its valve gear; compound engine and its theory; triple and multiple expansion engine; steam turbine; refrigeration; elevators and their management; cost of power; steam engine troubles; electric power and electric plants. 487 pages, 405 engravings. 3rd Edition. Price =$3.00=

=Steam Engine Catechism.= By ROBERT GRIMSHAW.

This unique volume of 413 pages is not only a catechism on the question and answer principle but it contains formulas and worked-out answers for all the Steam problems that appertain to operation and management of the Steam Engine. Illustrations of various valves and valve gear with their principles of operation are given. Thirty-four Tables that are indispensable to every engineer and fireman that wishes to be progressive and is ambitious to become master of his calling are within its pages. It is a most valuable instructor in the service of Steam Engineering. Leading engineers have recommended it as a valuable educator for the beginner as well as a reference book for the engineer. It is thoroughly indexed for every detail. Every essential question on the Steam Engine with its answer is contained in this valuable work. 16th Edition. Price =$2.00=

=Steam Engineer's Arithmetic.= By COLVIN-CHENEY.

A practical pocket-book for the steam engineer. Shows how to work the problems of the engine room and shows "why." Tells how to figure horsepower of engines and boilers; area of boilers; has tables of areas and circumferences; steam tables; has a dictionary of engineering terms. Puts you on to all of the little kinks in figuring whatever there is to figure around a power plant. Tells you about the heat unit; absolute zero; adiabatic expansion; duty of engines; factor of safety; and a thousand and one other things; and everything is plain and simple--not the hardest way to figure, but the easiest. 2nd Edition. Price =50 Cents=

=Engine Tests and Boiler Efficiencies.= By J. BUCHETTI.

This work fully describes and illustrates the method of testing the power of steam engines, turbines and explosive motors. The properties of steam and the evaporative power of fuels. Combustion of fuel and chimney draft; with formulas explained or practically computed. 255 pages, 179 illustrations. Price =$3.00=

=Horsepower Chart.=

Shows the horsepower of any stationary engine without calculation. No matter what the cylinder diameter of stroke, the steam pressure of cut-off, the revolutions, or whether condensing or non-condensing, it's all there. Easy to use. accurate, and saves time and calculations. Especially useful to engineers and designers. Price =50 Cents=

~STEAM HEATING AND VENTILATION~

=Practical Steam, Hot-Water Heating and Ventilation.= By A. G. KING.

This book is the standard and latest work published on the subject and has been prepared for the use of all engaged in the business of steam, hot-water heating, and ventilation. It is an original and exhaustive work. Tells how to get heating contracts, how to install heating and ventilating apparatus, the best business methods to be used, with "Tricks of the Trade" for shop use. Rules and data for estimating radiation and cost and such tables and information as make it an indispensable work for everyone interested in steam, hot-water heating, and ventilation. It describes all the principal systems of steam, hot-water, vacuum, vapor, and vacuum-vapor heating, together with the new accelerated systems of hot-water circulation, including chapters on up-to-date methods of ventilation and the fan or blower system of heating and ventilation. Containing chapters on: I. Introduction. II. Heat. III. Evolution of artificial heating apparatus. IV. Boiler surface and settings. V. The chimney flue. VI. Pipe and fittings. VII. Valves, various kinds. VIII. Forms of radiating surfaces. IX. Locating of radiating surfaces. X. Estimating radiation. XI. Steam-heating apparatus XII. Exhaust-steam heating. XIII. Hot-water heating. XIV. Pressure systems of hot-water work. XV. Hot-water appliances. XVI. Greenhouse heating. XVII. Vacuum vapor and vacuum exhaust heating. XVIII. Miscellaneous heating. XIX. Radiator and pipe connections. XX. Ventilation. XXI. Mechanical ventilation and hot-blast heating. XXII. Steam appliances. XXIII. District heating. XXIV. Pipe and boiler covering. XXV. Temperature regulation and heat control. XXVI. Business methods. XXVII. Miscellaneous. XXVIII. Rules, tables, and useful information. 367 pages, 300 detailed engravings. 2nd Edition--Revised. Price =$3.00=

=Five Hundred Plain Answers to Direct Questions on Steam, Hot-Water, Vapor and Vacuum Heating Practice.= By ALFRED G. KING.

This work, just off the press, is arranged in question and answer form; it is intended as a guide and text-book for the younger, inexperienced fitter and as a reference book for all fitters. This book tells "how" and also tells "why". No work of its kind has ever been published. It answers all the questions regarding each method or system that would be asked by the steam fitter or heating contractor, and may be used as a text or reference book, and for examination questions by Trade Schools or Steam Fitters' Associations. Rules, data, tables and descriptive methods are given, together with much other detailed information of daily practical use to those engaged in or interested in the various methods of heating. Valuable to those preparing for examinations. Answers every question asked relating to modern Steam, Hot-Water, Vapor and Vacuum Heating. Among the contents are: The Theory and Laws of Heat. Methods of Heating. Chimneys and Flues. Boilers for Heating. Boiler Trimmings and Settings. Radiation. Steam Heating. Boiler, Radiator and Pipe Connections for Steam Heating. Hot Water Heating. The Two-Pipe Gravity System of Hot Water Heating. The Circuit System of Hot Water Heating. The Overhead System of Hot Water Heating. Boiler, Radiator and Pipe Connections for Gravity Systems of Hot Water Heating. Accelerated Hot Water Heating. Expansion Tank Connections. Domestic Hot Water Heating. Valves and Air Valves. Vacuum Vapor and Vacuo-Vapor Heating. Mechanical Systems of Vacuum Heating. Non-Mechanical Vacuum Systems. Vapor Systems. Atmospheric and Modulating Systems. Heating Greenhouses. Information, Rules and Tables. 200 pages, 127 illustrations. Octavo. Cloth. Price =$1.50=

~STEEL~

=Steel: Its Selection, Annealing, Hardening, and Tempering.= By E. R. MARKHAM.

This work was formerly known as "The American Steel Worker," but on the publication of the new, revised edition, the publishers deemed it advisable to change its title to a more suitable one. It is the standard work on Hardening, Tempering, and Annealing Steel of all kinds. This book tells how to select, and how to work, temper, harden, and anneal steel for everything on earth. It doesn't tell how to temper one class of tools and then leave the treatment of another kind of tool to your imagination and judgment, but it gives careful instructions for every detail of every tool, whether it be a tap, a reamer or just a screw-driver. It tells about the tempering of small watch springs, the hardening of cutlery, and the annealing of dies. In fact, there isn't a thing that a steel worker would want to know that isn't included. It is the standard book on selecting, hardening and tempering all grades of steel. Among the chapter headings might be mentioned the following subjects: Introduction; the workman; steel; methods of heating; heating tool steel; forging; annealing; hardening baths; baths for hardening; hardening steel; drawing the temper after hardening; examples of hardening; pack hardening; case hardening; spring tempering; making tools of machine steel; special steels; steel for various tools; causes of trouble; high-speed steels, etc. 400 pages. Very fully illustrated. Fourth edition. Price =$2.50=

=Hardening, Tempering, Annealing, and Forging of Steel.= By J. V. WOODWORTH.

A new work treating in a clear, concise manner all modern processes for the heating, annealing, forging, welding, hardening and tempering of steel, making it a book of great practical value to the metal-working mechanic in general, with special directions for the successful hardening and tempering of all steel tools used in the arts, including milling cutters, taps, thread dies, reamers, both solid and shell, hollow mills, punches and dies, and all kinds of sheet-metal working tools, shear blades, saws, fine cutlery, and metal-cutting tools of all description, as well as for all implements of steel both large and small. In this work the simplest and most satisfactory hardening and tempering processes are given.

The uses to which the leading brands of steel may be adapted are concisely presented, and their treatment for working under different conditions explained, also the special methods for the hardening and tempering of special brands.

A chapter devoted to the different processes for case-hardening is also included, and special reference made to the adaptation of machinery steel for tools of various kinds, Fourth edition. 288 pages. 201 illustrations. Price =$2.50=

~TRACTORS~

=The Modern Gas Tractor.= By VICTOR W. PAGÉ, M.E.

A complete treatise describing all types and sizes of gasoline, kerosene and oil tractors. Considers design and construction exhaustively, gives complete instructions for care, operation and repair, outlines all practical applications on the road and in the field. The best and latest work on farm tractors and tractor power plants. A work needed by farmers, students, blacksmiths, mechanics, salesmen, implement dealers, designers, and engineers. Second edition, revised and enlarged. 504 pages. Nearly 300 illustrations and folding plates. Price =$2.00=

~TURBINES~

=Marine Steam Turbines.= By DR. G. BAUER and O. LASCHE. Assisted by E. LUDWIG and H. VOGEL.

Translated from the German and edited by M. G. S. Swallow. The book is essentially practical and discusses turbines in which the full expansion of steam passes through a number of separate turbines arranged for driving two or more shafts, as in the Parsons system, and turbines in which the complete expansion of steam from inlet to exhaust pressure occurs in a turbine on one shaft, as in the case of the Curtis machines. It will enable a designer to carry out all the ordinary calculation necessary for the construction of steam turbines, hence it fills a want which is hardly met by larger and more theoretical works. Numerous tables, curves and diagrams will be found, which explain with remarkable lucidity the reason why turbine blades are designed as they are, the course which steam takes through turbines of various types, the thermodynamics of steam turbine calculation, the influence of vacuum on steam consumption of steam turbines, etc. In a word, the very information which a designer and builder of steam turbines most requires. Large octavo, 214 pages. Fully illustrated and containing eighteen tables, including an entropy chart. Price, net =$3.50=

~WATCH MAKING~

=Watchmaker's Handbook.= By CLAUDIUS SAUNIER.

No work issued can compare with this book for clearness and completeness. It contains 498 pages and is intended as a workshop companion for those engaged in watch-making and allied mechanical arts. Nearly 250 engravings and fourteen plates are included. This is the standard work on watch-making. Price =$3.00=

~WELDING~

=Automobile Welding with the Oxy-Acetylene Flame.= By M. KEITH DUNHAM.

Explains in a simple manner apparatus to be used, its care, and how to construct necessary shop equipment. Proceeds then to the actual welding of all automobile parts, in a manner understandable by every one. _Gives principles never to be forgotten._ Aluminum, cast iron, steel, copper, brass, bronze, and malleable iron are fully treated, as well as a clear explanation of the proper manner to burn the carbon out of the combustion head. This book is of utmost value, since the perplexing problems arising when metal is heated to a melting point are fully explained and the proper methods to overcome them shown. 167 pages, fully illustrated. Price =$1.00=

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=Everyday Engineering=

A monthly magazine devoted to practical mechanics for everyday men. Its aim is to popularize engineering as a science, teaching the elements of applied mechanics and electricity in a straightforward and understandable manner. The magazine maintains its own experimental laboratory where the devices described in articles submitted to the Editor are first tried out and tested before they are published. This important innovation places the standard of the published material very high, and it insures accuracy and dependability.

The magazine is the only one in this country that specializes in practical model building. Articles in past issues have given comprehensive designs for many model boats, including submarines and chasers, model steam and gasoline engines, electric motors and generators, etc., etc. This feature is a permanent one in this magazine.

Another popular department is that devoted to automobiles and airplanes. Care, maintenance, and operation receive full and authoritative treatment. Every article is written from the practical, everyday man, standpoint rather than from that of the professional.

The magazine entertains while it instructs. It is a journal of practical, dependable information given in such a style that it may be readily assimilated and applied by the man with little or no technical training. The aim is to place before the man who leans toward practical mechanics, a series of concise, crisp, readable talks on what is going on and _how it is done_. These articles are profusely illustrated with clear, snappy photographs, specially posed to illustrate the subject in the magazine's own studio by its own staff of technically-trained illustrators and editors.

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+-----------------------------------------------------------------+ | TRANSCRIBER'S NOTES | | | | General remarks: | | There are some differences in wording between the Table of | | Contents, the lists of sections per chapter, and the actual | | section titles. Their meaning is clear, and they have been | | left as they were in the original work. | | Page 56, table: Fig. 8 in the first column does not refer to | | Fig. 8 in this work. | | The original work does not have a Figure 89. | | Page 303, table: it is uncertain what "free with kerosene" | | means, there may be a word omitted. | | Page 544, entirely censored. It is not clear what this page | | originally contained (possibly a table), since text and | | numbering of illustrations are uninterrupted. The text | | "CENSORED" has been moved to after the first paragraph of the | | section on Mercedes Engines. | | The List of Illustrations does not occur in the original work.| | | | Changes made: | | The text of the original work (including inconsistencies in | | accents, spelling, hyphenation and lay-out, and differences | | between the main text, illustrations and advertisements) has | | been followed, except when listed below. Only some minor | | obvious typographical errors have been corrected silently. | | Where the author used x for multiplication, this has been | | replaced by × in the body of the text (not in the | | advertisements or illustrations). | | The illustrations have been moved so as not to disrupt the | | flow of the text. | | Engine and aircraft types are not always named consistently in| | the original; Curtiss engine O X 2, OX-2 and 0X2 have all | | been changed to OX-2, Curtiss aircraft JN4 and JN-4 to JN-4. | | Multi-page tables: repeated headings have been removed, and | | the tables treated as one consecutive table. | | Page 22: "The product of" has been moved into the first | | formula. | | Page 25: "When B × r = M" changed to "When P × r = M". | | Page 74: ".225 ÷ 775 = .2905" changed to ".225 ÷ .775 = | | .2905". | | Page 137 (caption): "Bavary" changed to "Baverey" as | | elsewhere. | | Page 172: "evidently" changed to "evident". | | Page 214: "drop to O" changed to "drop to 0". | | Page 248: "actual from a common" changed to "actuated from a | | common". | | Page 256: "values" changed to "valves". | | Page 280: "Fig. 6" changed to "Fig. 112". | | Page 306: "Fig. 127, B" changed to "Fig. 127, C" (2nd | | reference). | | Page 324: "Rhone" changed to "Le Rhone" as elsewhere. | | Page 334: "Check values" changed to "Check valves". | | Page 364: "LeRhone" changed to "Le Rhone" as elsewhere. | | Page 390: "Fig. 62, D" changed to "Fig. 168, B". | | Page 408: "Stilson" changed to "Stillson" as elsewhere. | | Page 490: "both valves" changed to "both halves". | | Page 514: "standard ratio is 5.3" changed to "standard ratio | | is 5:3". | | Page 529: "gallons per minute 1,400 R. P. M." changed to | | "gallons per minute at 1,400 R. P. M." | | Page 546: "Hispano Suiza" changed to "Hispano-Suiza" as | | elsewhere. | | Page 556: "Diameter of crank-shaft, 56 mm." changed to | | "Diameter of crank-shaft, 55 mm." | | Page 7 (advertisements): "Hazlehurst Field" changed to | | "Hazelhurst Field". | | Page 21 (advertisements): "Rhose Island Compound" changed to | | "Rhode Island Compound". | | Index: "Shebler" changed to "Schebler", "camshaft" to | | "cam-shaft", "wristpin" to "wrist-pin", etc. (all as in text).| +-----------------------------------------------------------------+