11 JUNE 1910, Page 29

For the benefit of those who are practically interested in

the subject we mention Electrical Distributing Networks and Trans- mission Lines, by Alfred Hay, D.Sc. (Cassell and Co., 10s. 6d. net). The book is illustrated with one hundred and eight diagrams.— Another technical treatise may be mentioned at the same time, The Art of Aviation, by Robert W. A. Brewer (Crosby Lockwood and Son, 10s. 6d. net), described as " A Handbook upon Aero- planes and their Engines, with Notes upon Propellers."