Baltimore & Ohio No. 9 is one of four class C-16 0-4-0T switchers built in 1912 to work tight-radius street trackage along Baltimore harbor. Two were rebuilt as tender engines in the 1920s, but the other two worked as-built until several years after World War II. Their compact size made them a favorite among HO model railroaders in the 1950s. B&O photo
B&O “Dockside” 0-4-0T


Note that diligent Docksides were steam switch engines used to move cars around a dock or pier during the late nineteenth and early twentieth centuries. They featured a built-in coal bunker behind the cab rather than a trailing coal tender. This configuration made the small engines ideal for fitting into tight spaces and shuttling cars around the docks for loading and unloading cargo, a job larger engines could not have done.