Little is known of the Schaeffer, Bunce and Marvin (S.B.M.) steam parts factory in Lockport, NY. Apparently the Neff Steam Buggy contained an engine from the S.B.M. factory.
There is an artist's contemporary drawing of an S.B.M. Steamer in the Standard Catalog of American Cars
SACA Forum , Phorum 5, It's Like Fast and Stuff. Posts by Don Anger, Peter Brow, and David K. Nergaard