| ALCO introduced its "Century" series of locmotives in 1963, and the largest model in the initial catalog was designated the C628. Southern Pacific, impressed with the performance of the demonstrator set sent around by ALCO, purchased a group of twenty-five of the massive units (Nos. 4845-4869) in April, 1965. The railroad also acquired the four demonstrator units, numbering them 4870-4873. Then, only a couple of months later on July 1, 1965, the Southern Pacific adopted an entirely new numbering scheme for its locomotives, and the new C628s became the 7100-7128. In this photograph, taken during the short period in the spring of 1965 when the ALCOs carried their first numbers, Nos.4855, 4850, 4852 are approaching the end of their difficult run over the Sierra Nevada Mountains. |