(1)Wireless Pictures and Television: a Practical Description of the Telegraphy of Pictures, Photographs, and Visual Images (2)Television (Seeing by Wire or Wireless)

Abstract

(1) APPLIED photo-electricity has perhaps developed more rapidly than any other branch of applied physics. The discoveries of outstanding importance which have resulted from photo-electric, observations have stimulated the production of improved apparatus, and this has had a healthy reaction upon practical applications. Of these, telephotography and television are among the most interesting. Of the former, Mr. Thorne Baker was one of the most distinguished pioneers, and it is well to have a book on the subject from his pen. The various methods of picture transmission, such as those of Bakewell, Caselli, Charbonelle, Korn, Belin, and others, are described, but considerably more might well have been said about the code method by which Sanger Shepherd transmitted the race for the America Cup. A great deal is naturally said about selenium, and most of it correctly, though the date of discovery of its light-sensitiveness is given as 1861 instead of 1872, and the very prevalent mistake is made of describing it as particularly sensitive to red light, the great response to which is solely due to the abundance of energy in the red end of the spectra of most terrestrial sources.

(1)Wireless Pictures and Television: a Practical Description of the Telegraphy of Pictures, Photographs, and Visual Images.

By T. Thorne Baker. Pp. x + 188. (London: Constable and Co., Ltd., 1926.) 6s. 6d. net.

(2)Television (Seeing by Wire or Wireless).

By Alfred Dinsdale. Pp. 62. (London: Sir Isaac Pitman and Sons, Ltd., 1926.) 2s. net.