Diderot was a scientist. He studied and collected information which was compiled for scientific journals. He drew sketches and diagrams of his observations of flowers, plants, animals, insects, musical instruments, architecture, machinery and anatomy. The list goes on and on. Diderot is attributed to one of the most prolific journals of science, technology and art ever produced. Diderot, however, did not engrave his own plates. His plates were engraved by several different engravers, such as Bernard. Since Diderot is the one attributed with the work, we know little about the engravers. The engravers simply transferred Diderots work onto the plates. Diderots plates were very popular and were reproduced in several different editions as well as in several different sizes. He produced such a large volume of work that it would have been impossible for one engraver to do all of his plates, so there were several different engravers working on his plates. The differences in the way the engravers name appears on the plate simply denotes a different edition or publication.