A text-book of assaying

Silver is widely diffused, and has been found in most mining districts. It occurs native in sufficient quantity to constitute one of the chief ores of the metal. It also occurs...

Copper occurs native in large quantities, especially in the Lake Superior district; in this state it is generally pure. More frequently it is found in combination. The ores of c...

In assaying, more especially products direct from the mine, there is always found, when the rock is siliceous, a quantity of white sandy-looking substance, insoluble in acids, w...

Iron rusts or oxidises very readily, and, consequently, is rarely found in the metallic state in nature; such native iron as is found being generally of meteoric origin or imbed...

Alumina, the oxide of aluminium (Al_{2}O_{3}), is found in nature fairly pure in the mineral corundum; transparent and coloured varieties of which form the gems sapphire and rub...

Tin occurs in nature as cassiterite (containing from 90 to 95 per cent. of oxide of tin), which mineral is the source from which the whole of the tin of commerce is derived. Tin...

The chief source of the arsenic of commerce is arsenical pyrites, or mispickel, which contains about 45 per cent. of arsenic (As). Arsenic also occurs as a constituent of severa...

Oxygen occurs in nature in the free state, forming 23 per cent. by weight, or 21 per cent. by volume of the atmosphere; but, since it is a gas, its presence is easily overlooked...

Manganese occurs mainly as black oxide (MnO_{2}) in the mineral pyrolusite; and, in a less pure form, in psilomelane and wad. The value of the ore depends rather on the percenta...

~Acetic Acid~, H[=A=c] or C_{2}H_{4}O_{2}. (sp. gr. 1.044, containing 33 per cent. real acid).--An organic acid, forming a class of salts, acetates, which are for the most part...

Sulphur occurs native in volcanic districts, and is mined in Sicily, Italy, and California in considerable quantities. Combined with metals (sulphides), it is common in all mine...

These have been already described as those in which the results are got by measuring, either--(1) the volume of a reagent required to complete some reaction, or (2) the volume o...

"No more enduring Memorial of Professor Rankine could be devised than the publication of these papers in an accessible form.... The Collection is most valuable on account of the...

Assaying has for its object the determination of the quantities of those constituents of a material which add to or detract from its value in the arts and manufactures. The meth...

The relation of the weight of a substance to its volume should be kept in mind in all cases where both weight and volume are dealt with. Students are apt to imagine that on mixi...

The methods of assaying are best classed under two heads, Gravimetric and Volumetric, in the former of which the final results are weighed, whilst in the latter they are measure...

The Tables may almost claim to be exhaustive, and embody and collate all the most recent data established by experimentalists at home and abroad. The volumes will be found inval...

~Weighing.~--The system of weights and measures which we have adopted is the French or metric system; in this the gram (15.43 grains) is the unit of weight; the only other weigh...

"The new edition of Mr. Fidler's work will again occupy the same CONSPICUOUS POSITION among professional text-books and treatises as has been accorded to its predecessors. The i...

In _dry assays_ the metal is almost always separated and weighed as metal; in _wet_ gravimetric assays the metal is more usually weighed in the form of a definite compound of kn...

Formulæ and equations are a kind of short hand for expressing briefly and in the language of the atomic theory the facts of chemical composition and reaction. The convenience of...

"Prof. Cole treats of the examination of minerals and rocks in a way that has never been attempted before ... DESERVING OF THE HIGHEST PRAISE. Here indeed are 'Aids' INNUMERABLE...

GENERAL CONTENTS.--General Properties of Gems: Their Natural Characters, Occurrence, Application, and Uses.--Detailed Description of Particular Gems: The Diamond, Rubies, Sapphi...

*** "The aim of this work is to provide the student with a graded course of work leading from Simple Quantitative Analysis up to the Technical Quantitative Methods. It has been...

*** From the fact of the Author's having, for some years, had charge of the Main Drainage Works of the Northern Section of the Metropolis, the chapter on LONDON will be found to...

~THE MEAN DENSITY OF THE EARTH:~ An Essay to which the Adams Prize was adjudged in 1893 in the University of Cambridge. By J.H. POYNTING, Sc.D., F.R.S., Late Fellow of Trinity C...

ABRIDGED CONTENTS.--Introduction.--Definition.--Chemical Nature of Ferments.--Influence of External Factors.--Mode of Action.--Physiological Action.--Secretion.--Importance of F...

~A MANUAL OF CIVIL ENGINEERING:~ Comprising Engineering Surveys, Earthwork, Foundations, Masonry, Carpentry, Metal Work, Roads, Railways, Canals, Rivers, Waterworks, Harbours, &...

GENERAL CONTENTS.--Introduction.--Properties of the Metals.--Combustion.--Fuels.--Refractory Materials.--Furnaces.--Occurrence of the Metals in Nature.--Preparation of the Ore f...

SILVER--Detection 87 Dry assay 87 (1) Scorification 88 (2) Pot assays, average ores 90 " ores with metallic oxides 91 " ores with metallic sulphides 91 Explanatory notes on the...

*** Dr. Phipson's work presents, amidst much which is of interest to the Scientist and the General Reader alike, a short _résumé_ of his discovery of the origin of Atmospheric O...

CONTENTS.--The Nature of Sound and its chief Characteristics.--The Velocity of Sound in Air and other Media.--Reflection and Refraction of Sound.--Frequency and Pitch of Notes.-...

Table of atomic weights and other constants 433 Table for converting degrees of the centigrade thermometer into degrees of Fahrenheit's scale 435 Tables showing strengths of aqu...

COPPER--Introductory 175 Dry assay 176 Valuation of copper ores 181 Wet methods 183 (1) Electrolytic assay 184 Volumetric methods 194 (1) Cyanide method 194 (2) Iodide method 19...

IRON 231 Gravimetric determination 233 Permanganate and bichromate methods 234 Stannous chloride method 244 Colorimetric determination 247 NICKEL 251 Dry assay 251 Electrolytic...

ALUMINA 314 THORIA 317 ZIRCONIA 317 CERIUM 318 LANTHANUM AND DIDYMIUM 319 YTTRIA 319 BERYLLIA 319 LIME 320 STRONTIA 324 BARYTA 326 MAGNESIA 328 THE ALKALIES 330 SODIUM 334 POTAS...

INTRODUCTORY. Page Object of assaying 1 Sampling 1 Drying: determination of moisture 5 Calculation and statement of results 7 Laboratory books and report forms 9 Quantity to be...