Radio Broadcast (May-Oct 1922)

440 Radio Broadcast have given explicit directions for constructing transmitters and receivers which (so far as one can judge from the almost obvious faults in the suggested instruments) they have probably never tried to build and certainly never succeeded in working. In contrast to this sort of thing are two helpful books by M. B. Sleeper, entitled "Construction of Radio Phone and Telegraph Receivers for Beginners"", and " Design Data for Radio Transmitters and Receivers "i^; full working details for building a modern variometer type receiver (together with some interesting comments on radio telephony) will be found in "The How and Why of Radio Broadcasting"^^ by Arthur H. Lynch; and much information of utility is given by E. E. Bucher in "The Wireless Experimenter's Manual "i-*. A number of special subjects in the application of radio have been treated individually. " Radiodynamics"^^ by B. F. Miessner tells an interesting story of the control of distant mechanisms by means of wireless waves; "Wireless Transmission of Photographs "^^ by M. J. Martin describes many unusual experiments along the line which the title indicates; and "The Alexanderson System for Radio Telegraph and Radio Telephone Transmission"^^ by E. E. Bucher will interest any one who would enjoy exploring a modern high-powered trans-oceanic wireless station. Another special subject, which on account of its importance has received much attention by authors, is the vacuum tube now in such wide use. Elementary books describing its action as detector, amplifier, and oscillator are "The Oscillation Valve''^^ by R. D. Bangay, and "The ABC of Vacuum Tubes in Radio Reception "^^ by E. H. Lewis, both of which are clear and generally accurate. A somewhat less recent book on the same subject, which, however, gives an easily understood graphical description of the working of the device, is Bucher's "Vacuum Tubes in Wireless Communication".^'' For the advanced or scientifically trained student "The Thermionic Vacuum Tube and its Applications"-^ by H. J. Van der Bijl will be found a splendid treatise. Two other highly technical books on tubes are "The Thermionic Valve and its Developments in Radio Telegraphy and Telephony "^^ by J. A. Fleming, and "Thermionic Tubes in Radio Telegraphy and Telephony"-^ by John ScottTaggart. The former gives much historical matter of interest and value, as well as Professor Fleming's mathematical analyses of tube action; the latter is a very recent publication which describes present day British practice in the design and construction of valve outfits. Two other rather specialized books which will be of greatest use only to the technical student are "Telephony without Wires "^^ by P. R. Coursey and "Continuous Wave Wireless Telegraphy"-^ by W. H. Eccles. The first of these is quite different from the purely popular accounts of wireless telephony; it treats the radiotelephone technically as a division of radio signaling and assumes that the reader is fairly well familiar with wireless telegraphy. The second book is a full engineering development of the electrical theory of continuouswave circuits and instruments, including vacuum tubes. Having passed to the technical publications in radio, we must now consider those which go into the subject in a general but somewhat advanced way. The non-technical reader will have difficulty in getting very much from most of these books, but any one with even a small mechanical or electrical aptitude or education will be able to dig out a good deal of immense value. F. K. Vreeland's book called " Maxwell's Theory and Wireless Telegraphy"-®, containing a translation of the famous paper by Poincare, is not abstruse; the presentation of the principles underlying modern radio is vivid and easily read, so that the book, though nearly twenty years old, is interesting, to-day. Another of the older books which still is attractive is the "Principles of Wireless Telegraphy"-^ by Dr. G. W. Pierce; here the emphasis is placed upon the action of resonant circuits and receiving instruments. A somewhat later publication is Zenneck's "Wireless Telegraphy,"-^ translated by A. E. Seelig, which is a classical work on the fundamentals of radio design and practice. Another radio classic is Professor J. A Fleming's "Principles of Electric Wave Telegraphy and Telephony"-^, which first appeared in 1906 but which has been brought up to 1919 in a revised fourth edition; this volume is an exhaustive historical, theoretical and descriptive treatment of the development of radio signaling. In the past year or two there have appeared three other general radio books, each of which is noteworthy in its particular classification. "Electric Oscillations and Electric Waves''^" by Professor G. W. Pierce is a highly technical discussion of the theories and operations under