BOOMERANG, a weapon of the Australian aborigines and other peoples, chiefly used as a missile. The word is taken from the native name used by a single tribe in New South Wales. It is not connected with the womera or spear-thrower. Two main types may be distinguished: (a) the return boomerang; (b) the non-return or war boomerang. Both types are found in most parts of Australia ; the return form was, according to General Pitt-Rivers, used in ancient Egypt; and a weapon closely resem bling the boomerang survives to the present day in north-east Africa, with allied forms made of metal (throwing knives) . In south India is found a boomerang-shaped instrument which can be made to return. The Hopis (Moquis) of Arizona use a non return form. The general form of both weapons is the same. They are sickle-shaped, and made of wood (in India of ivory or steel). The thickness is about *th of the breadth, which again is nth of the length, the last varying from 6in. to 3 or 4f t.
The return boomerang, which may have two straight arms at an angle of from 70° to 12o°, but in Australia is always curved at an angle of 90° or more, is usu ally i to eft. in span, and weighs some 8oz. ; the arms have a skew, being twisted 2° or 3° from the plane running through the centre of the weapon, so that B and D (see fig.) are above it, A and E below it; the ends AB and DE are also to some extent raised above the plane of the weapon at C; the cross section is asymmetrical, the upper side in the figure being convex, the lower flat or nearly so ; this must be thrown with the right hand. The non-return boomerang has a skew in the opposite direction, but is otherwise similar.
The peculiarity of the boomerang's flight depends mainly on its skew. The return boomerang is held vertically, the concave side forward, and thrown in a plane parallel to the surface of the ground, as much rotation as possible being imparted to it. It travels straight for 3o yds. or more, with nearly vertical rotation; then it inclines to the left, lying over on the flat side and rising in the air; after describing a circle of 50 or more yards in diameter it returns to the thrower. Some observers state that it returns after striking the object; it is certainly possible to strike the ground without affecting the return. Throws of iooyds. or more, before the leftward curve begins, can be accomplished by Aus tralian natives, the weapon rising as much as 15o ft. in the air and circling five times before returning. The non-return type may also be made to return in a nearly straight line by throwing it at an angle of 45° ; normally it is thrown like the return type and will then travel an immense distance. No accurate measure ments of Australian throws are available, but an English throw of i8o yds. has been recorded, compared with the same thrower's 7o yds. with the cricket ball.
The war boomerang in an expert's hand is a deadly weapon, and the lighter hunting boomerang is also effective. The return boom erang is chiefly used as a plaything or for killing birds, and is often as dangerous to the thrower as to the object at which it is aimed.
See Pitt-Rivers (Lane Fox) in Anthropological and Archaeological Fragments, "Primitive Warfare"; also in Journ. Royal United Service Inst. xii. No. 51; British Ass. Report (1872) ; Catalogue of Bethnal Green Collection, p. 28 ; Buchner in Globus, lxxxviii., 39. 63 ; G. T. Walker in Phil. Trans. cxc. 23 ; Wide World Mag. ii. 626 ; Nature, xiv. 248, lxiv. 338, Brough Smyth, Aborigines of Victoria, i. 310-29; Roth, Ethnological Studies.