From David Hartley
Bath September 6 1791
May I beg the favour of you to give me your assistance officially, and as an old friend, towards obtaining letters patent in the united states of America, for the improvement of one of the most universal and important manufactures for the uses of life, that can exist in any country in the world; I mean the manufacture of all edged instruments of steel; than which none is more extensive or important, in every use and convenience of human life. The papers annexed to this letter will explain this point fully to you. I have letters patent for the sole and exclusive right of the invention in this Country.
I have a copy now before me of the American act for granting letters patent, and have endeavored to accomodate my application to the terms of that act. The specification annexed is the same upon which the letters patent in this Country have been granted. I have endeavored to explain the principle, and the application of the principle which constitutes the invention, in the most precise, and scientific, and intelligible terms; by which any intelligent workman, or adept person in the art and manufacture of steel, may be able to apply and use the same hereafter. If the petition, or any other branch of the application should be defective, according to the mode of your country, I will beg the favour of you to give me proper instructions, by which I may transmitt any amended or more formal application. Our friend Mr. Hammond, now minister to your Country, and whom you will recollect to have known at Paris, will do me the favour to negotiate the correspondence and I heartily wish both to him and to you, the most cordial and unanimous negotiations, in all other points whatsoever, which may contribute to the happiness, peace and prosperity of our two Countries. I beg to be most sincerely and kindly remembered to all my friends, both diplomatic and personal, in your country. I am Dear Sir with the greatest respect ever most sincerely yours,
RC (DLC); at foot of text: “To The Honble. Thos. Jefferson Esqr. &c. &c. &c.”; endorsed by TJ as received 11 Nov. 1791 and so recorded in SJL.
On 24 Feb. 1792 a patent was granted to David Hartley for his invention for “Hardening and tempering steel” (List of Patents Granted…from April 10, 1790, to December 31, 1836 [Washington, 1872]).