Page:Collier's New Encyclopedia v. 04.djvu/167

LEFT FIBEABMS 137 riBE ENGINE and this when turned comes in contact with a spring which opens and closes the circuit at each tooth, thus producing a signal at the central station. The number of the signal box is usually indicated by the arrangements of teeth and spaces and in that way the fire is lo- cated. Access to the crank or chain by which the signal is communicated is ob- tained either by a key or by twisting the door handle or by breaking the glass — this last being the method most in vogue in large cities. Telegraph instruments connecting with headquarters for the use of firemen are often attached. The sig- nal may be registered on a Morse re- cording instrument or by some similar device. In some districts there is an apparatus by which the signal results in the ringmg of tower l^lls or the sounding of steam-whistles. The last method, now supplemented by electricity, was formerly in general use, but the development of the electric telegraph has resulted in greater speed and in many simplifications. From the middle of the 19th century telegraph boxes have been with great velocity, and not infrequently passing unbroken across the sky until lost in the horizon. They differ frora ordinary meteors, probably, more in vol- ume and brilliancy than in any other dis- tinctive characteristic. FIRE ENGINE, a machine employed for throwing a jet of water for the pur- pose of extinguishing fires. This name was formerly applied to the steam en- gine. Machines for the extinguishing of fires have been used from a very early date. They were employed by the Romans, and are referred to by Pliny; but he gives no account of their con- struction. Hero of Alexandria, in his treatise on pneumatics — written prob- ably about 150 years before the Christian era — proposition 27, describes a machine which he calls "the siphons used in con- flagrations." It consisted of two cyl- inders and pistons connected by a recip- rocating beam, which raises and lowers the pistons alternately, and thus, with the aid of valves opening only toward the jet, projects the water from it, but not FIRE APPARATUS — ELECTRIC STORAGE BATTERY ENGINE in use in Boston, and improvements such as the non-interfering pull and succes- sive feature have brought the fire-alarm system to its present perfection. FIREARMS. See AMMUNITION; Ar- tillery; Explosives; Gun Powder; Ordnance; Etc. FIREBALL, a ball filled with powder or other combustibles, intended to be thrown among enemief- and to injure by explosion, or to set fire to their works. Bombs and grenades were thus employed in the World War (1914-1918). A popular name applied to a certain class of meteors which exhibit them- selves as globular masses of light moving in a continuous stream, as the pressure ceases at each alternation of the stroke. The first application of the steam fire engine was made when the Argyle Rooms in London were burned in 1830. Float- ing fire engines have been constructed and worked by steam. The steam fire engines have been greatly improved, and steam of more than 100 pounds pressure on the square inch can be raised in seven minutes after making the fire. Some of these engines throw a jet to a vertical heisrht of about 200 feet, or can drive water horizontally through half a mile of pipe. Gasoline motor-driven engines now iareely in use can be started in- stantly and make 35 miles an hour. The