H. Bloecker, Grand Haven, Michigan
H. G. Trout
H. G. Trout Engine Works, Buffalo, New York
H. G. Trout, Buffalo, New York
H. G. Trout, Buffalo, New York (King Iron Works)
H. Widdop & Co., Ltd
H.G. Trout
H.G. Trout, Buffalo, New York
Harkness & Moore, Cincinnati, Ohio
Harlan & Hollingsworth
Herreshoff
Hooven, Owens, Rentschler, Hamilton, Ohio
Hyslop & Roland, Canada, Ontario, Chatham