Complex sentence: From 1908-1914 the Bullfrog Goldfield Railroad (also serving the mines around Beatty) was combined into the T&T, and then combined again in 1918 after the demise of the Las Vegas & Tonopah Railroad.
Split into simpler sentences: From 1908-1914 the T&T and the Bullfrog Goldfield Railroad (also serving the mines around Beatty, Nevada) were combined under T&T. They were combined again in 1918 after the demise of the Las Vegas & Tonopah Railroad.