Fuyard (Fr.). A runaway; a coward. Un corps fuyard, a regiment that has been in the habit of running away.
Fuze. In gunnery, is a contrivance for igniting the bursting charge in a hollow projectile at any point of its flight. The simplest classification of fuzes is the [time fuze], the [percussion fuze], and the [concussion fuze], which are usually defined as follows:
Fuze, Concussion. Is a fuze that is operated by the shock of discharge, or the shock of impact, excluding direct percussion effects. It is especially applicable to hollow spherical projectiles. The usual difference between the concussion and percussion fuze is, that the former explodes no matter what point of the projectile strikes, whereas the latter requires the projectile to strike at or near the front end; but these are exceptions to the rule.
Fuze, Percussion. As shown below, is a fuze that receives no flame from the charge in the gun, but at the moment of impact a flame is generated by means of fulminates, which produces the explosion of the charge in the shell. Most varieties of this fuze consist essentially of a brass or pewter fuze-plug, or case which contains an iron or steel plunger terminating in a nipple which carries a common percussion-cap; the plunger is held in its place at the lower end of the fuze-plug by a collar-screw, wire, or other device; when the projectile strikes the plunger breaks loose, and by its inertia is driven forward with such force as to explode the cap and ignite the charge. This form of fuze is used for rifle-shells.
Fuze, Time. This fuze is composed of a case of paper, wood, or metal, inclosing a column of burning composition ignited by the charge in the gun; it burns for a certain time, at the end of which the flame is communicated to the bursting charge of the projectile. This fuze is used for both shells and case-shot.
Fuze, Blasting. A fuze used to fire charges in mines and quarries. It consists usually of a flexible tube filled with a slow-burning composition. The tube is made of various materials, and is usually waterproof. In Beckford’s fuze the composition is encased in flax, which is covered with gutta-percha, and wound with varnished tape. This fuze is used extensively in England.
Fuze-Composition. See [Laboratory Stores].
Fuze, Electric. A fuze ignited by the passage of an electric current. It is used for firing torpedoes, for the simultaneous discharge of guns and charges in mining. The principle used is the heating of the wire by the current at a point of resistance. The point of resistance is called the bridge. Being surrounded by a priming of powder or other explosive, its sudden heating causes ignition in the fuze. The bridge is made in various ways,—by connecting the current wires by a fine platinum wire; by passing the current through a chemical mixture rendered conducting by containing a salt of copper; also by filing the main wire nearly in two, and rubbing the cut with a lead-pencil.
Fuze-implements. Are the fuze-cutter, fuze-setter, fuze-mallet, fuze-saw, etc. See [Implements].
Fuze, Safety. A name given to a blasting fuze filled with quick-burning composition, but sufficiently long to be ignited at a safe distance from the charge.