"Single jaw" chain wrench - in the "ancestry" of the AGRIPPA pipe and fittings chain wrench. The specifications describe the side catches for the chain in the context of Booth and Redfield's June 13, 1893 patent no. 499,508 and Bufford's Nov. 3, 1903 patent no. 743,058. Patent no. 773,773 represents a further stage in evolution of the design.
Arthur S. Browne - patent attorney