Mitchell, it has now acquired a considerable degree of celebrity, the following minute description of its construction and properties, illustrated by the accompanying cut, may not be uninteresting. The extract
appeared some years since in the United Service Journal and is quoted in "Bennett's Travels in New South Wales":—
"The boomerang may be formed of any tough, heavy piece of wood, and is about three-eighths of an inch thick in the middle, gradually tapering off towards the extremities, and rounded on each side from the centre until brought to an edge. Construction:—Let A B E be the arc of a circle; the chord A D E = 18 inches; the perpendicular, B D = 17 inches; the width, B C = 3 inches. Thus constructed, the centre of gravity will fall exactly on the edge of its concave surface at C. When used as an offensive weapon it is usually thrown with the convex side outwards, but when intended to return it is held in the reverse position, although it will probably act in either position if properly managed."
For the latter purpose, however, it should be thrown from the hand at a considerable elevation (45 degrees), with a sudden jerk, so as to combine with the projectile force a rapid rotation round its centre of gravity. The rotation acts constantly in opposition to its line of flight, so that if a similar rotation could
