FUZE, or FUSE (abbreviation of fusee, from Fr. fusil, gun, steel for striking fire, It., ML. focile, steel for striking fire). The name of a variety of devices employed for firing explosives in military shells and mines and in blasting operations, etc. The simplest form of fuze, and the one which is most familiar, consists of a rope like tube filled with some slow-burning compound, one end of which is inserted in the explosive, and to the other end of which the light is applied. Such fuzes are made to burn at a certain rate of speed, and the time of explosion can, therefore, be regulated definitely by varying the length of the fuze. The Bickford match, which is used in blasting, burns at the rate of from two feet to four feet per minute. In modern practice blasts are most generally fired by electric fuzes. These are of two general classes. In both two naked copper wires pass through a cork or plug of some non-conducting material, and project inside a metal cylinder in the open end of which the plug is inserted. In tension fuzes the ends of the wires are not connected, and in quantity fuzes the ends of the large copper wires are con nected by a very fine wire, commonly of platinum. The metal cylinder is filled with some explosive compound, commonly fulminate of mercury, which explodes with a detonation. The outer ends of the two copper wires are connected with two wires which lead to the poles of a battery or other electrical generator, often a magnetic machine.
In operation, the metal cylinder with its ex ploding charge is inserted in the mine or blast to be fired, and the wires are connected with the electric generator. Upon completion of the cir cuit the current passes through the explosive compound in the detonator, forming a spark in the tension fuze and heating the fuze wire in the quantity fuze, and in either case causing the compound to explode and thus explode the mine or blast. Electric fuzes are used for firing sub merged mines in warfare. By means of the elec tric fuze a large number of mines or blasts can be fired simultaneously. See BLASTING.
Fuzes for projectiles are either time or per cussion, or a combination of both. Percussion fuzes generally have a plunger held by a safety ring or other device away from a cap of ful minate until, by the shock of discharge, they are armed, and the plunger left free to run for ward, when the shell strikes its target, and strike the cap. Time fuzes have a plunger held safe by a pin which is taken out when inserted in the gun; the discharge then shears off a frail sup port (the plunger lugs) and drives the plunger on to the cap at once, igniting a train of powder (time train) which burns during flight. Com
munication of flame to charge can be made only through the connecting tube, a small hole punched at a point corresponding to the time desired before explosion. The percussion prin ciple is generally combined with this to insure explosion on impact if the time train should fail to act, and the mechanism which is shown in the illustration is generally situated at the base of the fuze. • In spherical shell, a train of powder pressed into a wooden tube was cut to length proportion ate to time of bursting. Ignited at the outer end by discharge, this tube conveyed the com bustion to the charge. For ricochet fire over water, a water-cap of brass with a zigzag chan nel prevented extinction by immersion. An im proved fuse, chiefly used for spherical shell, was the Bormann. It was of pewter and was punched on a time scale. Greater accuracy was obtained by more uniform burning of the better time train.
Consult Bruff, Ordnance and Gunnery (New York, 1900). See also Pfto.marmEs; SHRAPNEL. FYFFE, fif, CHARLES ALAN (1845-92). An English historian, born at Blackheath, England, and educated at Balliol College, Oxford, where he graduated in 1868. He took his M.A. in 1870, and in the following year was elected a fellow of University College, and later was appointed bursar, which position he held for many years. He acted as war correspondent for the London Daily News during the early months of the Franco-Prussian War, and in the same capacity was in Paris during the Commune, narrowly escaping execution as a spy. He studied law at Lincoln's Inn and the Inner Temple in 1873 76, and in 1877 was admitted to the bar, but never practiced. In 1875 he published a small History of Greece, in a series of History Primers, which was well received. This success encour aged him to attempt a larger work, and he began writing his History of Modern Europe, which was published in three volumes in 1880. 1886, and 1890. It is a vigorous and careful account of the political history of Europe from the outbreak of the French Revolution to the Treaty of Berlin in 1878, and as a clear, con cise, and well-proportioned sketch of this period it has not been surpassed. Fyffe was a Radical in politics, was one of the founders of the Free Land League, and was an unsuccessful candidate for Parliament from Oxford in 1885.