Plate CXVII (117) from the second edition monograph on the steam engine and steam navigation by Thomas Tredgold and W. S. B. Woolhouse. The first edition, published in 1838, consisted of two volumes and titled, 'The Steam Engine: Its Invention and Progressive Improvement, an Investigation of its Principles, and its Application to Navigation, Manufactures, and Railways.' The second volume consisted of only plates. In the later edition, published 1845, only volume 2 was published under the title: 'Illustrations of Steam Machinery and Steam Naval Architecture.' The print is of a section view of the US Mail Boat 'Neptune' showing the engine and accommodations.
