Fecha de publicación: 18/02/1914 Fuente: WIPO "pollen" 4164. Pollen, A. H., and Isherwood, H. Feb. 18. Order apparatus.-An electric order telegraph of the wheatstone-bridge type comprises two instruments of identical construction, shown in Fig. 1, one being placed at the transmitting and one at the receiving end of a signalling line. The iron casings 1 are water-tight and capable of resisting rough usage. The electrical connexions are such that the galvanometers 13 on each instrument are deflected unless the transmitter- and receiver-pointers agree. The pointer on each instrument moves integrally with a nut 6 which can be raised or lowered by the screw 7 turned by means of the handle 8. The series of resistances 12 is connected across the mains and is tapped at one of the contacts 4 by the contact 5, which is connected through the two galvanometers 13 in series to the corresponding contact 5 of the other instrument. If the pointers of the two instruments do not agree, the two contacts 5 are at different potentials and the galvanometer needles are both deflected. Bell circuits are provided so that upon operation of the transmitter pointer notice may be given for the receiver pointer to be moved until the galvanometers indicate agreement.