AN INGENIOUS FIRE ALARM.

Dominion, Volume 2, Issue 570, 27 July 1909, Page 6

AN INGENIOUS FIRE ALARM.

The _"A.8.C." Fire, Alarm, bo called after tljie , initial letters of the names' of its invenAllan;. manager'of the '.Petbne Workshops; Bowling,, an operator in the Workshops, and Carnegie, engineer on '■ the b.s. Star of New Zealand—is',an ingenious device, combining, to judge from a public test which was. carried out at the office-of tie. New Zealand Consolidated Company. \in- Mercer Street yesterday, the' ..'attributes ■ of. simplicity,' economy, and effectiveness:;;:' The test, was witnessed by a number of business, men of the city. \'rhe principle of the alarm, is based' on,the natural law of expansion' by heat.- .Copper, globes, surmounted by-a circular copper plate, are fixed to the. ceiling of Vrbom. and- connected;'■ somewhat after the'. Manner of a ! gas 'installation, by lengths .of piping,-■ one end! of which connects with an eleotrio battery. , In the , battery box is. a .U-shaped' tube, containing mercury, and the pipe referred to is inserted in one end, while at the '.other '.is inserted .the- terminal wire; of the .battery.' , Any; rise ?'in'the,temperature of the'air: of the room is'instantly communicated to the air inside the globes, and' the '• subsequent. expansion exerts a pressure, along the air in the tube, and forces the mer-cury-in" the-, battery : ,box up :until: "contact" is made with the terminal wire, and'the'bell.sets up a continuous alarm..- ,By a system, of installatipnv terminatiiig automatio regi»teriboard on the ground;floor,; it is possible to place the.whole of a'big warehouse under observation.■'■'. In; the "holds' of ■'. ships, where outbreaks of fire'are frequently, very difficult to locate, the device;.should; prove of;.material value.' ■:' . -■■■ :' '■,„. . •'•"■'.■■'..'; ; . ' •'■' '