In 1866, Henry Kirke Porter and John smith opened a machine shop in Pittsburgh and began producing light locomotives for industrial use under the name Smith & Porter. After a disastrous fire in 1871, the company dissolved. Both partners eventually went back into the locomotive business, with Smith forming the National Locomotive Works which specialized in narrow gauge engines. Henry Porter's company focused its efforts on building four-wheel saddle tank locomotives for industry. These were powered by steam, gasoline and diesel. The company also made a series of compressed air engines for use in mine haulage. Porter's business thrived and in 1906 delivered almost 400 locomotives. One reason for the company's success was a result of superior design that utilized a system of inter-changeable parts across the line. Thisfacilitated rapid assembly and delivery to customers, and easy maintenance over the life of the engine. Henry Porter continued to run the company until 1921 when he died at the age of 81. Despite a bankruptcy in 1939, H.K. Porter continued in business up until 1950 when it was liquidated.