Wireless Telegraphy for Military Purposes - Editorial

The second Paper deals with Prof. Braun’s apparatus for military signalling. Here, in a remarkably portable form, is arranged powerful apparatus capable of operating without the earthing of the air-wire across a distance of 50 miles on land. A 5 H.P. benzine engine drives a dynamo whose current is transformed to yield a 16 in. spark. This spark occurs between balls in the primary circuit of a Tesla coil. The air-wire, suspended by balloon, is in series with the secondary of the Tesla transformer; but, instead of being earthed, it is connected to a large insulated plate. The generating plant is virtually a Poldhu in miniature. Evidently, Braun, like Marconi, has been converted to the high potential methods introduced by Tesla. Braun has freed himself from the earth, however, and has thus produced a system endowed to the fullest with that mobility so urgently demanded in modern warfare.