The locomotive was built by Baldwin in 1837 for the U&S which gave it the name Alert. It worked almost a decade before being sold in 1848 to the Galena and Chicago Union Railroad. The G&CU renamed it Pioneer and used it in the construction of the G&CU until 1850, when it was loaned to the Chicago, Burlington and Quincy Railroad for work laying the first track in Chicago that summer. Pioneer was returned and became its road work locomotive. After the G&CU was merged into the Chicago and North Western (C&NW), the locomotive remained in service until it was retired in 1875 at West Chicago, IL [1]