The Digital Bridges Project Digitized 19th century bridge engineering documents. Luckily for people like me, they've collected links to all the illustrations on one page. See for instance an amazing chronological series of pictures documenting the construction in 1892 of the 330 feet high, 3000 foot long, Pecos Viaduct in Texas.
posted on Mar 25, 2006 - View this thread

19th century mechanical models for teaching the principles of kinematics, the geometry of motion. Includes images and descriptions, QT movies of some of the models in motion, javascript simulations, and an online library of historical mechanical and engineering texts in html and pdf, including da Vinci's Madrid Codices, and Charles Babbage on On a Method of Expressing by Signs The Action of Machinery.
posted on Apr 18, 2005 - View this thread