Nut Cracking Anvil
The study experimented with the processing of nuts, and the first step in the process was, of course, cracking the nuts. To do this nuts were placed, one at a time, on stone or an anvil stone and then struck with a smaller hammer stone. As nuts were cracked in this manner a pit developed in the lower stone; the pit deepened as additional nuts were cracked, and this facilitated the cracking process since nuts were held rather stationary in this seat.
Government Printing Office The Official Gazette of the United States Patent Office (Washington, DC: Government Printing Office, 1895)