THE STONE AGE — PAST AND PRESENT. 199 



a chisel, an axe, or an adze. Wlienj however, the cutting edge 

 is hollowed as in a gouge, it is no longer possible to use it as 

 an axe, though it retains the other two possible uses of chisel 

 and adze. The water-worn pebble, in which a natural edge has 

 been made straighter and sharper by grinding-, may be taken 

 as the original and typical form of the celt. Rude South Ame- 

 rican tribes select suitable water-worn stones and rub down 

 their edges, sometimes merely grasping them in the hand to 

 use them, and sometimes mounting them in a wooden handle; 

 and axes made in this way, by grinding the edge of a suitable 

 pebble, and fixing it in a withe handle, are known in Australia. 

 Moreover, the class to which this almost natural instrument 

 belongs, that, namely, which has a double-convex cross sec- 

 tion, is far more numerous and universally distributed than the 

 double-flat, concavo-convex, triangular, or other forms. 



Where artificially-shaped celts are found only chipped over, 

 in high Stone Age deposits, as in Scandinavia, they are ge- 

 nerally to be considered as unfinished ; but when celts of hard 

 stone are found only ground near the edge, and otherwise left 

 rough from chipping, they may be taken as denoting a rude 

 state of art. Thus flint celts ground only near the edge are 

 found in Northern Europe, and even in Denmark ; but in general 

 celts of the hardest stone are found, during the Ground- Stone 

 Age, conscientiously ground and polished all over, and every 

 large celt of hard stone which is finished to this degree repre- 

 sents weeks or months of labou.r, done not so much for any 

 technical advantage, as for the sake of beauty and artistic 

 completeness. 



The primitive hammer, still used in some places, is an oval 

 pebble, held in the hand. Above this comes the natural peb- 

 ble, or the artificially-shaped stone, which is grooved or notched 

 to have a bent withe fastened round it as a handle, as our smiths 

 mount heavy chisels. Above this again is the highest kind, 

 the stone hammer with a hole through it for the handle. This 

 is not found out of the Old World, perhaps not out of Europe ; 

 and even the Mexicans, who in many things rivalled or excelled 

 the stone-workers of ancient Europe, do not seem to have got 

 beyond grooving their hammers. The stone axe proper, as 



