I bought this old cast iron T-wrench at a Pennsylvania flea market some time ago.
It is 6 1/2 inches high, and the top of the T is 8 inches long. There is a large "C D" monogram as the picture shows. The larger square opening, with its bolt-end accommodation, is 13/16 inches. The smaller square opening is 7/16 inches. The open hex end is 3/4 inch. The wrench, though cast, was provided with central ribs on both sides.
I cannot find out who made this wrench, or what its application was. Does anyone know?