Additional applications of the magnetic drum principle

Further applications of the magnetic drum principle using the magneto-cohesion effect described in a former paper are treated in detail. A description is given of a new form of siphon recorder, with a very small transit time, for high-speed reception on commercial circuits (beam stations). The shoe of the recorder is of special construction and the operating force for a current of 4 mA is about 4 lb., which is extremely large for a recording instrument. Owing to the rapidity of motion of the siphon lever it is possible to secure legible tape records when atmospheric disturbances are neither too severe nor too frequent. The procedure adopted in reading and transcribing messages at the central receiving station is given. Other applications of the magnetic drum principle to a delayed-action relay and to the checking of clocks by wireless signals are described. The thermionic valve circuits associated with the various devices are discussed and portrayed diagrammatically.