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CATALOGUE OF GOOD, PRACTICAL BOOKS tvely 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 de- scribed. have been or are used for the actual production of work, such, as parts of drill presses, lathes, patented machinery, typewriters, electrical apparatus, mechanical ap- pliances, brass goods, composition parts, mould products, sheet metal articles dron- forgings, jewelry, watches, medals, coins, etc. 531 pages. Price .... $4.00 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, and it saves you the trouble of bothering the boss 6th edition. 131 pages. Price................................50 cents MODERN MACHINE-SHOP CONSTRUCTION, EQUIPMENT AND MANAGE- MENT. 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 prac- tical 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. 400 large quarto pages. 225 original and specially-made illustrations. 2d. Revised and Enlarged Edition. Price..............................................$5.00 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 accom- plish what has already been accomplished are time and money LOST. The whole field of mechanics, every known mechanical movement, and practically every device is 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 follow- ing 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. 12th edition. 400 octavo pages. Price . . . $2.50 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 iu-st volume, which is more elementary in character, this volume contains illustrations and descriptions of many combinations of motions and of mechanical devices and 24