Chapter 2

The course of instruction, at the Stevens Institute of Technology, includes instruction in the trades to the extent above indicated. The original plan, as given below, included such a course of trade education for the engineer; but it was not at once introduced. The funds available from an endowment fund crippled by the levying of an enormous "succession tax" by the United States government and by the cost of needed apparatus and of unanticipated expenses, in buildings and in organization, were insufficient to permit the complete organization of this department. A few tools were gathered together; but skilled mechanics could not be employed to take up the work of instruction in the several courses. Little could therefore be done for several years in this direction. In 1875 the writer organized a "mechanical laboratory," with the purpose of attaining several very important objects: the prosecution of scientific research in the various departments of engineering work; the creation of an organization that should give students an opportunity to learn the methods of research most usefully employed in such investigations; the assistance of members of the profession, and business organizations in the attempt to solve such questions, involving scientific research, as are continually arising in the course of business; the employment of students who had done good work in their college course, when they so desire, in work of investigation with a view to giving them such knowledge of this peculiar line of work as should make them capable of directing such operations elsewhere; and finally, but not least important of all, to secure, by earning money in commercial work of this kind, the funds needed to carry on those departments of the course in engineering that had been, up to that time, less thoroughly organized than seemed desirable. This "laboratory" was organized in 1875, the funds needed being obtained by drawing upon loans offered by friends of the movement and by the "Director."

It was not until the year 1878, therefore, that it became possible to attempt the organization of the shop course; and it was then only by the writer assuming personal responsibility for its expenses that the plan could be entered upon. As then organized--in the autumn of 1878--a superintendent of the workshop had general direction of the trade department of the school. He was instructed to submit to the writer plans, in detail, for a regular course of shop instruction, and was given as assistants a skilled mechanic of unusual experience and ability, whose compensation was paid from the mechanical laboratory funds, and guaranteed by the writer personally, and another aid whose services were paid for partly by the Institute and partly as above. The pay of the superintendent was similarly assured. This scheme had been barely entered upon when the illness of the writer compelled him to temporarily give up his work, and the direction of the new organization fell into other hands, although the department was carried on, as above, for a year or more after this event occurred.

The plan did not fall through; the course of instruction was incorporated into the college course, and its success was finally assured by the growth of the school and a corresponding growth of its income, and, especially, by the liberality of President Morton, who met expenses to the amount of many thousands of dollars by drawing upon his own bank account. The department was by him completely organized, with an energetic head, and needed support was given in funds and by a force of skilled instructors. This school is now in successful operation. This course now also includes the systematic instruction of students in experimental work, and the objects sought by the writer in the creation of a "mechanical laboratory" are thus more fully attained than they could have possibly been otherwise. It is to be hoped that, at some future time, when the splendid bequest of Mr. Stevens may be supplemented by gifts from other equally philanthropic and intelligent friends of technical education, among the alumni of the school and others, this germ of a trade school maybe developed into a complete institution for instruction in the arts and trades of engineering, and may thus be rendered vastly more useful by meeting the great want, in this locality, of a real trade school, as well as fill the requirements of the establishment of which it forms a part, by giving such trade education as the engineer needs and can get time to acquire.

The establishment of advanced courses of special instruction in the principal branches of mechanical engineering may, if properly "dovetailed" into the organization, be made a means of somewhat relieving the pressure that must be expected to be felt in the attempt to carry out such a course as is outlined below. The post-graduate or other special departments of instruction, in which, for example, railroad engineering, marine engineering, and the engineering of cotton, woolen, or silk manufactures, are to be taught, may be so organized that some of the lectures of the general course may be transferred to them, and the instructors in the latter course thus relieved, while the subjects so taught, being treated by specialists, may be developed more efficiently and more economically.

Outlines of these advanced courses, as well as of the courses in trade instruction comprehended in the full scheme of mechanical engineering courses laid out by the writer a dozen years ago, and as since recast, might be here given, but their presentation would occupy too much space, and they are for the present omitted.

The course of instruction in this branch of engineering, at the Stevens Institute of Technology, is supplemented by "Inspection Tours," which are undertaken by the graduating class toward the close of the last year, under the guidance of their instructors, in which expeditions they make the round of the leading shops in the country, within a radius of several hundred miles, often, and thus get an idea of what is meant by real business, and obtain some notion of the extent of the field of work into which they are about to enter, as well as of the importance of that work and the standing of their profession among the others of the learned professions with which that of engineering has now come to be classed.

At the close of the course of instruction, as originally proposed, and as now carried out, the student prepares a "graduating thesis," in which he is expected to show good evidence that he has profited well by the opportunities which have been given him to secure a good professional education. These theses are papers of, usually, considerable extent, and are written upon subjects chosen by the student himself, either with or without consultation with the instructor. The most valuable of these productions are those which present the results of original investigations of problems arising in practice or scientific research in lines bearing upon the work of the engineer. In many cases, the work thus done has been found to be of very great value, supplying information greatly needed in certain departments, and which had previously been entirely wanting, or only partially and unsatisfactorily given by authorities. Other theses of great value present a systematic outline of existing knowledge of some subject which had never before been brought into useful form, or made in any way accessible to the practitioner. In nearly all cases, the student is led to make the investigation by the bent of his own mind, or by the desire to do work that may be of service to him in the practice of his profession. All theses are expected to be made complete and satisfactory to the head of department of Engineering before his signature is appended to the diploma which is finally issued to the graduating student. These preliminaries being completed, and the examinations having been reported as in all respects satisfactory, the degree of Mechanical Engineer is conferred upon the aspirant, and he is thus formally inducted into the ranks of the profession.

COURSE OF INSTRUCTION IN MECHANICAL ENGINEERING.

Robert H. Thurston--July, 1871.

I.

MATERIALS USED IN ENGINEERING.--Classification, Origin, and Preparation (where not given in course of Technical Chemistry), Uses, Cost.

_Strength and Elasticity_.--Theory (with experimental illustrations), reviewed, and tensile, transverse and torsional resistance determined.

_Forms_ of greatest strength determined. _Testing_ materials.

_Applications_.--Foundations, Framing in wood and metal.

FRICTION.--Discussion from Rational Mechanics, reviewed and extended.

_Lubricants_ treated with materials above.

Experimental determination of "coefficients of friction."

II.

TOOLS.--Forms for working wood and metals. Principles involved in their use.

Principles of pattern making, moulding, smith and machinists' work so far as they modify design.

Exercises in Workshops in mechanical manipulation.

Estimates of _cost_ (stock and labor).

MACHINERY AND MILL WORK.--Theory of machines. Construction. Kinematics applied. Stresses, calculated and traced. Work of machines. Selection of materials for the several parts. Determination of _proportions_ of details, and of _forms_ as modified by difficulties of construction.

Regulators, Dynamometers, Pneumatic and Hydraulic machinery. Determining _moduli_ of machines.

POWER, transmission by gearing, belting, water, compressed air, etc.

LOADS, transportation.

III.

HISTORY AND PRESENT FORMS OF THE PRIME MOVERS.

_Windmills_, their theory, construction, and application.

_Water Wheels_. Theory, construction, application, testing, and comparison of principal types.

_Air, Gas, and Electric Engines_, similarly treated.

STEAM ENGINES.--Classification. [Marine (merchant) Engine assumed as representative type.] Theory. Construction, including general design, form and proportion of details.

_Boilers_ similarly considered. Estimates of _cost_.

_Comparison_ of principal types of Engines and Boilers. Management and repairing. Testing and recording performance.

IV.

MOTORS APPLIED to Mills. Estimation of required power and of _cost_.

Railroads. Study of Railroad machinery.

Ships. Structure of Iron Ships and rudiments of Naval architecture and Ship propulsion.

PLANNING Machine shops, Boiler shops, Foundries, and manufactories of textile fabrics. Estimating _cost_.

LECTURES BY EXPERTS.

GENERAL SUMMARY of principal facts, and natural laws, upon the thorough knowledge of which successful practice is based; and general _resume_ of principles of business which must be familiar to the practicing engineer.

V.

GRADUATING THESES.

GRADUATION.

Accompanying the above are courses of instruction in higher mathematics, graphics, physics, chemistry, and the modern languages and literatures.

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IMPROVED DOUBLE BOILER.

The operation of boiling substances under pressure with more or less dilute sulphuric or sulphurous acid forms a necessary stage of several important manufactures, such as the production of paper from wood, the extraction of sugar, etc. A serious difficulty attending this process arises from the destructive action of the acid upon the boiler or chamber in which the operation is carried on, and as this vessel, which is generally of large dimensions, is exposed to considerable pressures, it is necessarily constructed of iron or some other sufficiently resisting metal. An ingenious method of avoiding this difficulty has been devised, we believe in Germany, and has been put into practice with a certain amount of success. It consists in lining the iron boiler with a covering of lead, caused by fusion to unite firmly to the walls of the boiler, and thus to protect it from the action of the acid. No trouble, it is stated, is found to arise from the difference in expansion of the two metals, which, moreover, adhere fairly well; but, on the other hand, we believe it does actually occur that the repairs to this lead lining are numerous, tedious, and costly of execution, so that the system can scarcely be regarded as meeting the requirements of the manufacturer. It is to secure all the advantages possessed by a lead-lined vessel, without the drawback of frequent and expensive repairs, that the digester, of which we annex illustrations, has been devised by Mr. George Knowles, of Billiter House, Billiter Street. It consists of a closed iron cylindrical vessel suitable for boiling under pressure, and containing a second vessel open at the top, and of such a diameter as to leave an annular space between it and the walls of the outer shell. This inner receiver, which may be made of lead, glass, pottery, or any other suitable material, contains the substance to be treated and the sulphurous acid or other solution in which it is to be boiled. The annular space between the two vessels is filled with water to the same level as the solution in the receiver, and the latter is provided with suitable pipes or coils, in which steam is caused to circulate for the purpose of raising the solution of the desired temperature, and effecting the digesting process. At the same time any steam generated collects in the upper part of the boiler, and maintains an equal pressure within the whole apparatus. Figs. 1 to 3 show the arrangement clearly. Within the boiler, a, is placed the receiver, b, of pottery, lead, or other material, leaving an annular space between it and the boiler; this space is filled with water. The receiver, b, is furnished with a series of pipes, in which steam or hot water circulates, to heat the charge to the desired temperature. These pipes may be arranged either in coils, as shown at d, Fig. 1, or vertically at d, Fig. 3. The latter are provided with inner return pipes, so that any condensed water accumulating at the bottom may be forced up the inner pipes by the steam pressure and escape at the top. The vessel is charged through the manhole, e, and the hopper, c, provided with a perforated cover, and is discharged at the bottom by the valve, f, shown in Figs. 2 and 3. The upper part of the boiler serves as a steam dome, and the pressure on the liquid in the receiver and on the water in the annular space is thereby maintained uniform. The necessary fittings for showing the pressure in the vessel, water level indicator, safety valve, cocks for testing solutions, etc., are of course added to the apparatus, but are not indicated in the drawing. The arrangement appears to us to possess considerable merit, and we shall refer to it again on another occasion, after experiments have been made to test its efficiency.--_Engineering_.

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THE GARDNER MACHINE GUN.

The mechanism by which the various functions of loading, firing, and extracting are performed is contained in a rectangular gun metal case, varying in dimensions with the number of barrels in the arm. In the single barrel gun the size of this case is 14 inches in length, 5½ inches in depth, and 2½ inches in width. The top of the box is hinged, so that easy access can be had to the mechanism, which consists of a lock, the cartridge carrier, and the devices for actuating them. In the multiple barrel guns, the frames which, with the transverse bar at the end, hold the barrels in place, form the sides of the mechanism chamber, in the front end of which the barrels are screwed. The mechanism is actuated by a cam shaft worked by a hand crank on one side of the chamber. By this means the locks are driven backward and forward, the latter motion forcing the cartridges into place, and the former withdrawing the empty cartridge case after firing. The extractor hook pivoted to the lock plunger rises, as the lock advances, over the rim of the case, but is rigid as the lock is withdrawn, so that the action is a positive one. The cartridges, which are contained in a suitable frame attached to the forward part of the breech chamber, pass through openings in the top plate of the latter, an efficient distribution being secured by means of a valve having a transverse motion. Each cartridge as it falls is brought into the axis of the barrel and the plunger, while the advance motion of the lock forces them into position. In the five-barrel gun illustrated by Fig. 3 the cartridge feeder contains 100 cartridges, in five Vertical rows of 20 cartridges each, and these are kept supplied, when firing, from supplementary holders. Fig. 1 shows the portable rest manufactured by the Gardner Gun Company. It consists of two wrought iron tubes, placed at right angles to each other; the front bar can be easily unlocked, and placed in line with the trail bar, from which project two arms, each provided with a screw that serves for the lateral adjustment of the gun. These screws are so arranged as to allow for an oscillating motion of the gun through any distance up to 15 deg. The tripod mounting, used for naval as well as land purposes, is shown in Fig. 2, which illustrates the two barrel gun complete. The five barrel gun, Fig. 3, is shown mounted on a similar tripod. The length of this weapon over all is 53.5 inches, the barrels (Henry system) are 33 inches long, with seven grooves of a uniform twist of one turn in 22 inches.

Gardener's five barrel gun in the course of one of the trials fired 16,754 rounds with only 24 jams, and in rapid firing reached a maximum of 330 shots in 30 seconds. The two barrel gun fired 6,929 rounds without any jam; the last 3,000 being in 11 minutes 39 seconds, without any cleaning or oiling.--_Engineering_.

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CLIMBING TRICYCLES.

The cycle trade is one which has been developed with great rapidity within the last ten years, and, like all new industries, has called forth a considerable amount of ingenuity and skill on the part of those engaged in it. We cannot help thinking, however, that much of this ingenuity has been misplaced, and that instead of striving after new forms involving considerable complication and weight, it would have been better and more profitable if manufacturers had moderated their aspirations, and aimed at greater simplicity of design; for it must be remembered that cyclists are, as a rule, without the slightest mechanical knowledge, while the machines themselves are subject to very hard usage and considerable wear and tear in traveling over the ordinary roads in this country. We refer, of course, more especially to tricycles, which in one form or another are fast taking the place of bicycles, and which promise to assume an important position in every day locomotion. Hitherto one of the chief objections to the use of the tricycle has been the great difficulty experienced in climbing hills, a very slight ascent being sufficient to tax the powers of the rider to such an extent as to induce if not compel him in most instances to dismount and wheel his machine along by hand until more favorable ground is reached. To obviate this inconvenience many makers have introduced some arrangement of gearing speeds of two powers giving the necessary variation for traveling up hill and on the level. We noticed, however, one machine at the exhibition which seemed to give all that could be desired without any gearing or chains at all. This was a direct action tricycle shown by the National Cycle Company, of Coventry, in which the pressure from the foot is made to bear directly upon the main axle, and so transmitted without loss to the driving wheels on each side, the position of the rider being arranged so that just sufficient load is allowed to fall on the back wheel as to obtain certainty in steerage. The weight of this machine is much less than when gearing is used, and the friction is also considerably reduced, trials with the dynamometer having shown that on a level, smooth road, a pull of 1 lb. readily moved it, while with a rider in the seat 4 lb. was sufficient. On this tricycle any ordinary hill can, it is stated, be ascended with great ease, and as a proof of its power it was exhibited at the Stanley show climbing over a piece of wood 8 in. high, without any momentum whatever. We understand that at the works at Coventry a flight of stairs has been erected, and that no difficulty is experienced in ascending them on one of these machines.--_The Engineer_.

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SUBMARINE EXPLORATIONS.

VOYAGE OF THE TALISMAN.

It was but a few years ago that the idea was prevalent that the seas at great depths were immense solitudes where life exhibited itself under no form, and where an eternal night reigned. To-day, thanks to expeditions undertaken for the purpose of exploring the abysses of the ocean, we know that life manifests itself abundantly over the bottom, and that at a depth of five and six thousand meters light is distributed by innumerable phosphorescent animals. Different nations have endeavored to rival each other in the effort to effect these important discoveries, and several scientific missions have been sent to different points of the globe by the English and American governments. The French likewise have entered with enthusiasm upon this new line of research, and for four consecutive years, thanks to the devoted aid of the ministry of the marine, savants have been enabled to take passage in government vessels that were especially arranged for making submarine explorations.

The first French exploration, which was an experimental trip, was made in 1880 by the Travailleur in the Gulf of Gascogne. Its unhoped for results had so great an importance that the following year the government decided to continue its researches, and the Travailleur was again put at the disposal of Mr. Alph. Milne Edwards and the commission over which he presided. Mr. Edwards traversed the Gulf of Gascogne, visited the coast of Portugal, crossed the Strait of Gibraltar, and explored a great portion of the Mediterranean. In 1882 the same vessel undertook a third mission to the Atlantic Ocean, and as far as to the Canary Islands. The Travailleur, however, being a side-wheel advice-boat designed for doing service at the port of Rochefort, presented none of those qualities that are requisite for performing voyages that are necessarily of long duration. The quantity of coal that could be stored away in her bunkers was consumed in a week, and, after that, she could not sail far from the points where it was possible for her to coal up again. So after her return Mr. Edwards made a request for a ship that was larger, a good sailer, and that was capable of carrying with it a sufficient supply of fuel for remaining a long time at sea, and that was adapted to submarine researches. The Commission indorsed this application, and the Minister of Instruction received it and transmitted it to Admiral Jauréguiberry--the Minister of the Marine--who at once gave orders that the Talisman should be fitted up and put in commission for the new dredging expedition. This vessel, under command of Captain Parfait, who the preceding year had occupied the same position on the Travailleur, left the port of Rochefort on the 1st of June, 1883, having on board Mr. Milne Edwards and the scientific commission that had been appointed by the Minister of Public Instruction. The Talisman explored the coasts of Portugal and Morocco, visited the Canary and Cape Verd Islands, traversed the Sea of Sargasso, and, after a stay of some time at the Azores, returned to France, after exploring on its way the Gulf of Gascogne (Fig.).