Qr How our Ancestors in the Stone Age  [November, 
the flake, then with a firm downward pressure of the point, a con- 
choidal fragment would be broken out almost always of the size 
desired. The point of the deer prong would then be advanced a 
short distance and the same operation repeated, until in a few 
minutes the flake was reduced to a straight line on one edge. As 
this operation broke all the chips from the under side of the flake, 
if left in this condition the arrowhead would be unequally pro- 
portioned, that is, the two cutting edges would not be in the cen- 
ter. He therefore with the side of the deer horn firmly rubbed 
back and forth the straight edge he had made on the flake until 
the sharp edge had been broken and worn down. The flake was 
now turned end for end in the palm of his hand and the chipping 
renewed. When completed an equal amount was taken from 
each side of the edge of the flake and the cutting edge was left 
in the center. It was now plain that the straight edge thus made 
was to be one side of the long isosceles triangle, the form of the 
arrowheads which is used by his tribe. 
With the flake of obsidian firmly held in the cushion of the 
left palm and the point of deer horn strongly pressed on the edge 
of the flake, the effect was the same as the blow which split the 
flake from the larger piece. While, however, he was not always 
sure of the effect of the blow in splitting off the large flakes out 
of which to make the arrowheads, he in no instance appeared to 
fail in breaking out with the point of deer-prong the exact piece 
desired. The soft thick pliable piece of tanned deer skin on which 
the flake in his left palm was held, may have added to the cushion, 
but seemed to serve no other purpose than to save his hand from 
being cut by the countless sharp chips as they were broken off. 
One of the long sides of the arrowhead having been thus formed, 
the flake was turned over and the other side formed in the same 
manner. As, however, very much more of the obsidian had to 
be chipped away, he brought more pressure upon the point and 
broke out larger chips until the flake began to assume the shape 
desired, when the same care was exercised as when the first 
-straight edge was made. In breaking out large or small chips 
the process was always the same. The pressure of the point of 
deer horn on the upper edge of the flake never appeared to break 
out a piece, which, on the upper side, reached beyond where the: 
point rested, while on the under side the chip broken out might 
leave a space of twice the distance. Invariably when a line of © 
