Crystal Palace International Electric Exhibition 1881-82

55 142.—J. Hay Athole Macdonald, la, Abercromby Place, Edinburgh. Automatic Fire Alarm. A strip of thin gutta- percha sheet is fastened as a bi'idge between two uprights; a metal bar rests on the gutta-percha. When the temperature rises the gutta-percha gives way under the weight of the bar, which falls between two metal springs and completes an electric dpcmt .Nave. 143.—McWhirter, Roberts, & Co., 249 to 251, East India Road, London. Makers of Telegraph Fittings, Signalling Lamps and Apparatus, Cutters, Lapping-wire, Fitters’ and Jointers' Tools, &Ct Eastern Gallery. 144—Donald Nicoll, 19, Devereux Court, Temple. Secret Com- munication Effectuator. A new system of secret coirespondence by electric telegraph (Post Office or Postal Cards) intended to super- sede ordinary cipher or code systems. Changes in the new system may be made daily by arrangement with correspondents, curiosity or treachery at the same time being defeated. Special education is not required as in the case of ancient cipher or code systems. European languages are alone used; the bewilderment of tele- graph. employés is avoided, and the meaning of the messages cannot be made out without the possession of duplicate instru- ments, registered 6 & 7 Vic. cap. 65, under the title of “ Secret Communication Effectuator/’ by the inventor, holder , oi “ une mention honorable pour telegrapbie electrique, Exposition Uni- verselle, Paris, 1867." The new system is brought within. I’eacli of the million, the price being Is. for each set of 6 plates : such, may be ordered of every stationer in the kingdom or colonies, or will be forwarded by post, plus only cost of stamps, 19, Devereux Court, Strand, London. Eastern Gallery. 145 .—J. Orme & Co., 65, Barbican, E.C. Electric Bells, Button Pushes, &c. &c. {See Advt.; p. 119.) Western Gallery. 146 .'—James M. Ormes, Hobace H. Eldred, Gr. L. Andris, 31, Queen Victoria Street, E.C. Hanning's Transmitter; Auto- matic Sub-Offices. Eastern Gallery. 147 .—E. Paterson, 76, Little Britain. Electric Signals for hotels, houses, mines, yachts, &c., with all accessories. {See Advt., p. 119.) South Nave and Southern Gallery. 148 .—T. Teale Powell, James Street, Harrogate, Yorkshire. Powell’s Electric Signalling on Railways, securing direct and interchangeable communication between passengers, guards,