right thickness for a mere. The natives[1] use stone hammers for chipping, flakes of trap or of some other hard rock for sawing, and blocks of sandstone and a micaceous rock for grinding and polishing. Obsidian is said to be used for boring jade. I have a flat piece of jade, apparently part of a thin hatchet, on one face of which two notches have been sawn converging at an angle of 135° and marking out what when detached and ground would have formed a curved ear-ring. It was given me by the late Mr. H. N. Moseley, who brought it from New Zealand.
There is another peculiarity to be seen in some of the green-stone hatchets and perforated axes, of which perhaps the most characteristic examples occur in Switzerland, though the same may occasionally be observed in British specimens. It is that the blocks of stone have been reduced into form, not only by chipping with a hammer, as is the case with flint hatchets, but by working upon the surface with some sort of pick or chisel, which was not improbably formed of flint. In some instances, where the hatchets were intended for insertion into sockets of stag's horn or other materials, their butt-end was purposely roughened by means of a pick after the whole surface had been polished. Instances of this roughening are common in Switzerland, rare in France, and rarer still in England. The greenstone hatchet found in a gravel-pit near Malton[2] (Fig. 81) has its butt-end roughened in this manner. The shaft-holes in some few perforated axes appear to have been worked out by means of such picks or chisels, the hole having been bored from opposite sides of the axe, and generally with a gradually decreasing diameter. In some rare instances the perforation is oval. The cup, or funnel-shaped depressions, in some hammer-stones seem to have been made in a similar manner. The inner surface of the shaft holes in perforated axes is also frequently ground, and occasionally polished. This has in most cases been effected by turning a cylindrical grinder within the hole; though in some few instances the grinding instrument has been rubbed backwards and forwards in the hole after the manner of a file. M. Franck de Truguet,[3] of Treytel, in Switzerland, thinks he has found in a lake-dwelling an instrument used for finishing and enlarging the holes. It is a fragment of sandstone about 212 inches long, and rounded on one face, which is worn by friction.
But, besides the mode of chipping out the shaft-hole in per-
