A B C of television; or, Seeing by radio; a complete and comprehensive treatise dealing with the theory, construction and operation of telephotographic and television transmitters and receivers; written especially for home experimenters, radio fans and students.. (1929)

CATALOGUE OF GOOD, PRACTICAL BOOKS APPLIED AERODYNAMICS. By G. P. THOMPSON. This is a scientific and mathematical treatise that has a special appeal to the student and engineer who are seeking exact information on the aerodynamics of heavier-than- air craft and data on airplane design testing. In addition to a very full discussion of the qualities which determine the speed and rate of climb of an aeroplane and the method by which they can be calculated, special attention is paid to stability —a problem now fairly well understood, and to controllability—our knowledge of which is at present in a much more elementary state. Attention is directed to the numerous directions in which further information is required, especially in the form of full-scale experiments. 312 pages (7 x 10). Illustrated with over 142 Diagrams and Graphic Charts. Price $5.00 GLOSSARY OF AVIATION TERMS —ENGLISH-FRENCH; FRENCH- ENGLISH. By MAJOR VICTOR W. PAGE, A.S., S.C.U.S.R., and LIEUT. PAUL MONTARIOL, of the French Flying Corps. A complete glossary of practically all terms used in aviation, having lists in both French and English with equivalents in either language. Price, . . 50 cents BOAT BUILDING MINIATURE BOAT BUILDING. By ALBERT C. LEITCH. Covering the construction of working models of racing sail and power boats by ama teurs. A concise and complete treatise written in understandable language covering marine model making in general and the specific design and construction of numerous famous miniature racing sail and power boats. The boats illustrated and described have been developed from an engineering point of view rather than from a toy angle. In this book the authors have illustrated and described step by step, the best model making practice, from the selection of the raw material to the completed boats. Com plete designs for steam power plants, including tubular boilers and blow torch for firing them. One, two and four cylinder engines are also fully described. 500 spe cially prepared engravings. 242 pages. Price $3.00 BRAZING AND SOLDERING BRAZING AND SOLDERING. By JAMES F. HOBART. The only book that shows you just how to handle any job of brazing or soldering that comes along; it tells you what mixture to use, how to make a furnace if you need one. Full of valuable kinks. The fifth edition of this book has just been published, and to it much new matter and a large number of tested formulae for all kinds of solders and fluxes have been added. Illustrated 35 cents SOLDERING AND BRAZING. By RAYMOND FRANCIS YATES. This treatise gives all the necessary "kinks" that will enable one to accomplish suc cessful soldering. If a mechanic has not succeeded in his spidering, this book may tell him just what he needs to produce good work—something that he may hereto fore have forgotten. Price 75 cents CHARTS BOILER ROOM CHART. By GEO. L. FOWLER. A chart — size 14x28 inches—showing in isometric perspective the mechanisms be longing in a modern boiler room. The various parts are shown broken or removed, BO that the internal construction is fully illustrated. Each part is given a reference number, and these, with the corresponding name, are given in a glossary printed at the sides 35 cents