Jefferson, Thomas (1743-1826) to Dr. James Mease [incomplete]
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Gilder Lehrman Collection #: GLC07145 Author/Creator: Jefferson, Thomas (1743-1826) Place Written: Monticello, Virginia Type: Autograph letter signed Date: 19 August 1803 Pagination: 1 p. ; 25.1 x 20.3 cm Order a Copy
States that he has received his letter and will answer the two inquiries he posed on the subject of the mould board for a plow at Monticello. Describes in detail design modifications that can be made to the mould board to improve the plow's results. Comments that though the plow will be improved, the results will not be as aesthetically pleasing as the original. Lower right corner of page is missing. There is some text loss, including half of Jefferson's signature.
Jefferson had an interest in improving farming technology. He designed a plow fitted with his improved wooden mould board that offered less resistance when pulled through the soil. In 1814 he began to have his mould boards cast in iron. Jefferson's moldboard was featured in Dr. James Mease's Domestic Encyclopedia (Philadelphia, 1803), and the French Society of Agriculture awarded Jefferson its gold medal and membership as a foreign associate.
Monticello Aug. 19.03
Dear Sir
I have duly received your favor of the 9th. and proceed to answer the two enquiries made in it on the subject of the Mould-board. the 1st. indeed as to the modifications of the simpler form of the mould board, is answered in the passage [inserted: of the Philos. transaction] where they are mentioned. these modifications are there described, & the reasons are stated which render them necessary. as to the 2d.enquiry respecting the casting them in iron, it was my intention when I wrote that paper to have had it done, but on conversing with judge Peters on the subject he told me he had tried the mould boards of that material & found them so [inserted: difficult to fix and] liable to be broke that he had given them up, & advised me against the attempt.
I have since thought of an alteration in the form of that mould board which would recommend it more to common opinion, and perhaps improve it. in the one described in the Philosophical transactions the toe of the mould-board is at a right angle with the bar and is lodged in a duplication of the hinder edge of the ring like a comb-case. but I would propose to make that duplication parallel with the fore-edge of the fin, and 2 or 3. I. back from it, consequently the mould board would be pointed at the toe, instead of being square. to do this, after the pyramidal block is cut out, the fore-right-corner of the block should be sawed off by a line leading from the fore-left corner parallel [inserted: with] the fore-edge of the wing. this being done the bevil is to be formed by exactly the same process as in the first description. the principle of this is rigorously the same with the first; it is only one of those accommodations of it to be different circumstances & views, which practice may produce. it will probably enter & pass on with less resistance. it will at the same time lose a beautiful & <text lost> -geous effect which I observed produced by the first form, [inserted: which] being <text lost> like a wedge, the earth of the furrow rising on it kept it steadil <text lost> without any warbling, and without any effort of the ploughman. <text lost> as smooth as that of a ship through the water in a steady wind <text lost> Accept my respectful & friendly salutations.
Th: Jefferson [end of signature cut-off]
Doctr. Maese
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