Scientific American, Vol. 5, No. 31 (April 1850)

1850 · 4 pictures

Patents · Claim · Stephenson · Ment · Locomotive · Twenty years · Color · Prepared india · Patent laws · Scientific American · Inclined plane · Cast Iron · Tyrian purple · Patent office · Sir john · Patent journal

Internet Archive · Public domain (published before 1931) · More from this library