Today in History - 1856

The ferrotype, or "tintype" was invented by Ohio chemistry professor Hamilton L. Smith of Gambier. Smith had made the first daguerreotype in Cleveland and had experimented with the photographic process while a professor at Kenyon College. With the assistance of a former student, Peter Neff, Jr., Smith perfected making an ambrotype on metal, which he patented on this date (patent #14,300). Smith later assigned his rights to the patent to William Neff and Peter Neff, Jr. This became the basis of a business for the Neffs, as they charged a fee for anyone using this process.

The tintype gained in popularity after the 1860s, largely due to competitive ferrotype firms, like that of another Ohioan, Victor Griswold, who held his own patent for the process, using a thinner sheet of metal. The Civil War made the tintype the most popular form of photography because of its durability, unlike the ambrotype, and its quick development time-one minute from exposure to finished product.

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