Power Transmission (Vol. 22, p. 224), illustrated, Mechanical, by Professor Dalby; Hydraulic, by Edward B. Ellington, chief engineer of the General Hydraulic Power Co., Ltd.; Pneumatic, by A. de W. Foote, superintendent of the North Star Mining Co., California; Pulley (Vol. 22, p. 641), illustrated, by Dr. Ernest G. Coker, professor of mechanical Engineering in the City and Guilds of London Technical College; Pump (Vol. 22, p. 645), illustrated; Brake (Vol. 4, p. 413), illustrated; Tool (Vol. 27, p. 14), with 79 illustrations, by Joseph G. Horner; Cranes (Vol. 7, p. 368), with 21 illustrations, by Walter Pitt; Elevators (Vol. 9, p. 263), illustrated, by G. F. Zimmer, author of Mechanical Handling of Material; Lubricants (Vol. 17, p. 89) by R. M. Deeley, joint author of Lubrication and Lubricants; Pneumatic Despatch (Vol. 21, p. 865) by H. R. Kempe, electrician to the General Post Office, London; Gyroscope and Gyrostat (Vol. 12, p. 769), illustrated, by Sir Alfred Greenhill; Motor Vehicles (Vol. 18, p. 914), with 37 illustrations—Light, by the Hon. C. S. Rolls, late managing director of the Rolls Royce Co., Ltd.; Heavy Commercial Vehicles, by Edward S. Smith, editor of The Commercial Motor; Railways, Locomotive Power (Vol. 22, p. 842) by Professor W. E. Dalby.

For the Electrical Engineer

The key article describing the general principles of electrical engineering is Electricity Supply (Vol. 9, p. 192), illustrated, by Emile Garcke, but at the immediate service of the electrical engineer there also stand Dynamo (Vol. 8, p. 764), with 42 illustrations, by C. C. Hawkins, author of The Dynamo; Power Transmission, Electrical (Vol. 22, p. 233) by Dr. Louis Bell, chief engineer, Electric Power Transmission Dept., General Electric Co.; Conduction, Electric (Vol. 6, p. 855), Conduction in Solids by Professor Fleming; in Liquids, by W. C. D. Whetham; in Gases, by Sir J. J. Thomson, a Nobel prize-winner and professor of experimental physics at Cambridge; Electrolysis (Vol. 9, p. 217) by W. C. D. Whetham; Electrokinetics (Vol. 9, p. 210), illustrated; Electrostatics (Vol. 9, p. 240); Electromagnetism (Vol. 9, p. 226), illustrated; Units, Physical, Electrical Units (Vols. 27, p. 740); Galvanometer (Vol. 11, p. 428), illustrated; Electrometer (Vol. 9, p. 234), illustrated; Amperemeter (Vol. 1, p. 879), illustrated; Voltmeter (Vol. 28, p. 206), illustrated; Ohmmeter (Vol. 20, p. 34), illustrated; Wattmeter (Vol. 28, p. 419)—all of these by Professor Fleming; Potentiometer (Vol. 22, p. 205); Accumulator (Vol. 1, p. 126), with 24 illustrations and diagrams, by Walter Hibbert, of the London Polytechnic; Transformers (Vol. 27, p. 173), with 15 illustrations and diagrams, and Wheatstone’s Bridge (Vol. 28, p. 584), illustrated, by Professor Fleming; Motors, Electric (Vol. 18, p. 910), by Dr. Louis Bell; Meter, Electric, (Vol. 18, p. 291), by Professor Fleming; Lighting, Electric (Vol. 16, p. 659), with 16 illustrations, by Professor Fleming, and a chapter on its commercial aspects, methods of charging, wiring of houses, testing meters, etc., by Emile Garcke; Telegraph (Vol. 26, p. 510), fully illustrated, Land and Submarine Telegraphy, by H. R. Kempe; Wireless Telegraphy, by Professor Fleming, and Commercial Aspects, by Emile Garcke; Telephone (Vol. 26, p. 547), illustrated, by H. R. Kempe and Emile Garcke; Traction, Electric (Vol. 27, p. 120), illustrated, by Professor Duncan. An admirable historical sketch of electricity will be found in Electricity (Vol. 9, p. 179), by Professor Fleming, which contains also an account of the development of electric theory.

American Practice in Mining

It is typical of the policy pursued in making the new Britannica that the Editor placed the mining section in the hands of American experts, since they are universally regarded as the best in the world. This entire section is a worthy monument to American learning and practice.

The key-article Mining (Vol. 18, p. 528), fully illustrated, is by Dr. Henry Smith Munroe, professor of mining in Columbia University. This covers every branch of the subject, but further discussion of its special phases is continued in Mineral Deposits (Vol. 18, p. 504) by Dr. James F. Kemp, professor of geology, Columbia University; Quarrying (Vol. 22, p. 712) by Dr. F. J. H. Merrill, formerly state geologist of New York; Ore-Dressing (Vol. 20, p. 238), illustrated, by Dr. R. H. Richards, professor of mining and metallurgy, Massachusetts Institute of Technology; Shaft-Sinking (Vol. 24, p. 766), illustrated; Boring (Vol. 4, p. 251), illustrated; Blasting (Vol. 4, p. 44), illustrated—the last three by Robert Peele, professor of mining in Columbia University.

The Metallurgical Section

Metallurgy (Vol. 18, p. 203) describes in outline the general sequence of operations. Assaying (Vol. 18, p. 776) is by Andrew A. Blair, formerly chief chemist U. S. Geological Survey. See also Metal (Vol. 18, p. 198). Metalography (Vol. 18, p. 202), illustrated, is an account of the new and important method of microscopical examination of alloys and metals by Sir William Chandler Roberts-Austen; and Francis H. Neville. Alloys (Vol. 1, p. 704), with unique photomicrographs of alloys and metals, is also by the authors of the article Metallography. Annealing, Hardening and Tempering (Vol. 2, p. 70), illustrated, is by Joseph G. Horner, who also writes Forging (Vol. 10, p. 663), which has 19 illustrations, Founding (Vol. 10, p. 743), with 11 illustrations, and Rolling-Mill (Vol. 23, p. 468), with 8 illustrations. The material on Fuel has already been mentioned. Furnace (Vol. 11, p. 358) describes and illustrates all the latest designs. Welding (Vol. 28, p. 501) is by J. G. Horner and Elihu Thomson, who writes on his own invention, Electric Welding.

The mining engineer or metallurgist will have in the new Britannica constantly at his elbow a complete series of articles dealing with the mining and metallurgy of all minerals and metals. Professor Howe’s exhaustive article Iron and Steel has already been noted in another part of this chapter. A few of the other important articles are Copper (Vol. 7, p. 103); Gold (Vol. 12, p. 192); Silver (Vol. 25, p. 112); Lead (Vol. 16, p. 314); Tin (Vol. 26, p. 995); Zinc (Vol. 28, p. 981); Manganese (Vol. 17, p. 569); Aluminum (Vol. 1, p. 767) by E. J. Ristori, member of Council, Institute of Metals. Safety-Lamp (Vol. 23, p. 998) is written by Hilary Bauermann. The latest mining statistics of all countries are to be found under their respective headings.

Biographies of Engineers