Nice threads

A nice little calculator from Lufkin.  Although there were clearly far more fastener sizes in 1935 (increasing by 1/64ths in diameter, rather than today's 1/16th), the gauge is still very handy.  Edward Lufkin was an American civil war vet who formed the E.T. Lufkin Board & Log Rule Manufacturing Co. in 1869.  He had sold out all of his interests in the company by the mid-1880's.  The brand is now owned by the giant conglomerate, Cooper Tools.