William Smith’s Strata Identified by Organized Fossils, published between 1816 and 1819, was one of the most important books in the development of stratigraphy; it was also significant in the evolution of paleontological art and illustration. For the first time, Smith organized fossil illustrations in plates according to the order of the strata. Each stratigraphic plate showed characteristic assemblages of fossils. The publication was a joint venture between Smith and James Sowerby and it was Sowerby who elevated the work into the realm of art. Smith had been influenced by the work of previous authors, in particular Robert Plot and John Morton, who, some 150 years earlier, had published texts illustrated by fossil engravings. The difference between these engravings and those of Sowerby shows the extent to which fossil illustration had evolved. Unlike previous work where the engravings were very mechanical, Sowerby’s were extraordinarily naturalistic. By means of subtle lines, stipple, and water coloring, Sowerby was able to achieve extremely realistic and aesthetically pleasing artwork. Unusually, many of Smith’s originals fossils are still intact and when photographs of these specimens are compared to the illustrations, the quality of Sowerby’s work is striking. Smith also selected earth-colors for the paper on which the illustrations were produced, with colors reflecting the strata in which the fossils were embedded. Although this technique had some disadvantages, it aimed to bridge the gap between science and art.