OF the numerous achievements of which the electrical engineer can boast, telegraphy is the one of which he has the greatest reason to be proud. If we combine with telegraphy the sister subject of telephony there can be little doubt but that by the application of these two sciences he has effected a greater revolution in human affairs than by all his successes in the way of heavy engineering. He may “electrify “our railways, especially the suburban lines, to the great advantage of both the travelling public and the shareholder, but he is still only doing for us in another way what the mechanical engineer has already accomplished. He may harness the great waterfalls and transmit their power over hundreds of miles to localities at which it can be more easily utilised, but he is only saving Mahomet the trouble of going to the mountain. He may provide for us in the arc lamp and the glow lamp the most efficient means of producing artificial light, but he is only supplying us with an alternative to the cheaper productions of the gas engineers. But with telegraphy he has ghen us something entirely new—an art which, whilst actually annihilating distance, virtually annihifates time. So familiar have we become with the oierations of the telegraphist that few probably ever realise how closely dependent upon them is every dettil of modern civilised life. “We speak of the twentieth century as being, or as promising to be, the electrical age, and we think of the railways, the lighting, and the development of power, whereas in reality it is the electrical age because of the telegraph and the telephone. If the vast network of thin wires which stretch over the civilised world like the threads of a spider's web were suddenly wiped out to-morrow, we should as suddenly realise with the non-appearance of the morning paper what it meant to be thrown back into the age before electricity. Telegraphy. By T. E. Herbert. Pp. xx + 912. (London: Whittaker and Co., 1906.) Price 6s. 6d. net. The Principles of Electric Wave Telegraphy. By Dr. J. A. Fleming. Pp. xix + 671. (London: Longmans, Green and Co., 1906.) Price 24s. net. Wireless Telegraphy. By Dr. Gustav Eichorn. Pp. x + 116. (London: Charles Griffin and Co., Ltd., 1906.) Price 8s. 6d. net. Wireless Telegraphy. By W. J. White. Pp. x + 173. (London: T. C. and E. C. Jack, 1906.) Price 1s. net.