Wireless Telegraphy and Telephony

Abstract

THE publication of the first number of a German year-book of wireless telegraphy and telephony affords an indication of the growing importance of this branch of electrotechnics. The volume before us is more of the character of an ordinary scientific magazine than of a year-book, since there is not really much attempt to summarise the progress during the past year, which have take it, is peculiarly the function of a year-book. This objection apart, the publication deserves praise on account of the merit of the articles which it contains. Of these the most important are one by Prof. F. Braun on directed wireless telegraphy, one by Dr. Simon on the production of undamped waves, and one by Prof. Fleming on some of the most recent developments.

Jahrbuch der drahtlosen Telegraphie und Telephonie.

Band i., Heft i. Edited by Dr. G. Eichorn. (Leipzig: S. Hirzel, 1907.) Preis fur den Band, 20 marks.

Wireless Telephony in Theory and Practice.

By E. Ruhmer. Translated by J. Erskine-Murray. Pp. xv + 224. (London: Crosby Lockwood and Son, 1908.) Price 10s. 6d. net.