Another interesting company tied to insulators is the H.K. Porter Co. Was started in 1866 by Henry Kirk Porter and John J. Smith (Smith & Porter Co.) to make industrial equipment. Railroad and mining companies hired them to make locomotives in 1867. In 1871 the company was destroyed by fire and Smith left. It was rebuilt in 1878 and renamed H. K. Porter Co. after Henry. Continued making locomotives until 1950 when it was purchased by Delta Star Electric Co and became H. K. Porter Co. Div of Delta Star Co. Inc. Where they made their quality tools (bolt cutters for one) and of course the loved or loathed plastic insulator. Here is a giveaway 6ft tape measure from H. K. porter Company Pittsburgh, PA.