When James Watt, working in Birmingham in the summer of 1778, succeeded in developing a method of copying letters by mechanical means, he did so in order to spare himself work. But he was soon convinced to patent the process and market the materials. James Watt & Co. received a patent in May, 1780, for a copy press that would soon change the lives of Franklin and many of his contemporaries.3

Watt & Co. advertised for subscriptions through various London stationers, the chief one being James Woodmason of Leadenhall Street. To their one-page “Proposals for Receiving Subscriptions, for an Apparatus, by which Letters or other Writings may be copied at once …,” they attached a sample (or “specimen”) which consisted of a single, copied sentence written in an elegant hand: “Time, Labour & Money are saved, Dispatch & Accuracy are attained, and Secrecy is preserved by this newly-invented Art of copying Letters and other Writings.”4

Woodmason, who had visited Franklin in June, 1779, and sold him an order of paper,5 must have sent him multiple copies of this proposal, to judge by the present letter. His cover letter, now missing, must also have described the copying process well enough for Franklin to have tried it himself (as he says here). The attempt apparently stimulated Franklin to recall a copying method he had devised years earlier in America. He demonstrated his method to the abbé Rochon, and their discussions inspired the abbé not only to improve upon it, but also, by mid-August, to invent an entirely new kind of engraving machine.

Franklin’s technique for “printing almost as quickly as one could write” is known to us only through the abbé’s reports, described below. It involved writing on paper with a gummy ink over which he sprinkled a powder of fine sand or iron filings. He ran this sheet through a rolling press, made a negative impression on a copper plate, and used that plate to produce duplicates. The method, although fast, produced copies “bien désagréables à la vue,” according to the abbé, who decided that Franklin’s method could be improved by writing directly on a specially varnished copper plate with a steel point, etching the writing into the plate with a nitric acid solution, and printing a negative copy. From this reverse imprint, one could make a positive copy by applying wetted paper and running it through a rolling press. (This last step was doubtless inspired by Watt’s method.) If multiple copies were desired, one could print any number of reverse sheets from the copper plate, and press a fresh sheet of copying paper onto each one.

Rochon soon wondered about the feasibility of mechanically engraving type. He invented a small machine that pressed individual letter-punches into a plate of copper, allowing for letter-spacing and line-spaces, which was capable of creating an entire page of text that would look like print. The process was quick, the machine was portable, and it could be operated by virtually anyone. Rochon anticipated that it would be particularly useful in the battlefield and on shipboard.

The abbé presented his engraving machine to the Academy of Sciences on August 19, opening his report by describing his conversations with Franklin about copying methods and admitting that he would never have become interested in the art of engraving had it not been for these discussions.6 The Academy enthusiastically endorsed it, and Rochon published a detailed description, along with several plates, in his Recueil de mémoires sur la mécanique et la physique (Paris, 1783).7 As for his method of copying handwriting, based on Franklin’s method, he explained it years later to Thomas Jefferson, who took careful notes.8