Nicolas-Jacques Conte
Nicolas-Jacques Conté (1755-1805) was a French engineer, scientist, and inventor.
An account of his life and work here [1]
Conté invented the modern pencil lead at a time when the French Republic was under economic blockade and unable to import graphite from Britain. Lazare Nicolas Marguerite Carnot asked Conté to create a pencil that did not rely on imported material. After several days of research, Conté had the idea of mixing powdered graphite with clay and pressing the material between two half-cylinders of wood. He received a patent for the invention in 1795, and formed la Société Conté to make them. He also invented the conté crayon. [2]
The Musée des Arts et Métiers have on display a form of dividing engine used for engraving series of accurately-space lines on printing plates, made in 1803, designed by Nicolas Jacques Conté and constructed by Antoine Clerc Gallet. See here. Conté was responsible for a publication on Napoleon's Egyptian campaign, and wishing to reduce the cost of producing the plates for printing the illustrations, he proposed using a machine to assist in engraving. It would engrave parallel lines, more or less pronounced, graduated to vary the density of the tones. The publication of the Description de l’Égypte in twenty volumes took place from 1808 to 1822.