“It is the large agricultural implements that I refer to as having been made from quartzite slabs, some of which are as much as sixteen inches long by six inches and seven inches wide at the spadeblade end. There are many smaller specimens of the same form and character that have been regularly flaked from chert, white waxy quartz, yellow and brown jasper, that do not exceed six or seven inches in length, their working ends highly polished by long use in digging. It is the large hoes and spades flaked from quartzite slabs that to me are evidence of a much higher degree of intelligence and skill than the most highly-finished spear- and arrow-points evince. Take an edge view of one of these large spades, and observe how accurately straight and free from wind the edge has been carried entirely around the implement, the flattening of one side and rounding the other; then observe that the long, flat, very slightly depressed, flakes have been thrown off at right angles to the edge, even to those curving around its digging or cutting end, which appear to have radiated from a common centre. If these flakes have been thrown off by blows so struck and directed as to preserve the cleanly lined edges, as the operator had carried them in his mind, a skill must have been acquired that we cannot approach. “In all the experiments that I have tried with a hammer, whether of stone, steel, soft iron, or copper, they have failed to produce the desired result; the seat of the flake is more conchoidal, shorter and deeper depressed, whereas the direct percussive pressure throws off the shape of flake that we find has been done in making these spades. If this mode has been resorted to, it necessarily required considerable ingenuity in devices for holding the stone slab firmly, while the pressure was being applied in the right direction. The wooden clamp described by Catlin may have been used. The simplest device that occurs to me that will answer the purpose is a block of wood planted in the ground, with its end grain up, cut on top into steps, the lower step having grooves parallel with the rise of the upper step; in one of these grooves the edge of the implement is placed, its back resting against the edge of the higher step as represented by the dotted lines showing the form of a spade. (See Fig. 18.) When in this position, presenting the proper angle to the operator, a man holds it firmly while another applies the pressure. A lower step and the back edge of the top are hollowed out to receive the work, while its lower end rests in an indentation in the lower step. In this manner a spade can be firmly held while its cutting end is being flaked. I do not present this as a mode that was practiced, but as a device that answers the purpose, and I judge to be within the capacity of the ancient flint-workers, of whom there is nothing left but their chips and finished work.