In addition to several other glass factories, Muncie attracted iron and steel mills, including the Republic Iron and Steel Company and the Midland Steel Company. (Midland became Inland Steel Company and later moved to Gary, Indiana.) Indiana Bridge Company was also a major employer. By the time the natural gas supply from the Trenton Gas Field had significantly declined and the gas boom ended in Indiana around 1910, Muncie was well established as an industrial town and a commercial center for east-central Indiana, especially with several railroad lines connecting it to larger cities and the arrival of automobile industry manufacturing after 1900.