CD 1040 close up vs. patent drawing

By Bill Meier; posted June 2, 2008

View Original (630 x 486) 55KB


Here is a close up of the [id=217010767; previous picture]. To the right of it, is the drawing from the patent for in, patented on January 3, 1871 by John Garity of East Birmingham, PA.

Pretty amazing... The patent discusses two types, one with a hex head for use with a wrench, and the other with a round head. Two examples of the former are known, and none of the latter.