Jethro Wood, Inventor of the Modern Plow.. Gilbert Frank

      Under date of July 3, 1796, Mr. Jefferson wrote to Jonathan Williams: “You wish me to present to the Philosophical Society the result of my philosophical researches since my retirement. But, my good Sir, I have made researches into nothing but what is connected with agriculture. In this way I have a little matter to communicate, and will do it ere long. It is the form of a mould-board of least resistance. I had some years ago conceived the principle of it, and I explained it then to Mr. Rittenhouse. I have since reduced the thing to practice, and have reason to believe the theory fully confirmed. I only wish for one of those instruments used in England for measuring force exerted in the drafts of different ploughs, etc., that I might compare the resistance of my mould-board with that of others. But these instruments are not to be had here. In a letter of this date to Mr. Rittenhouse I mention a discovery in animal history, very signal indeed, of which I shall lay before the society the best account I can, as soon as I shall have received some other materials collecting for me.

      “I have seen, with extreme indignation, the blasphemies lately vended against the memory of the father of American philosophy. But his memory will be venerated as long as the thunder of heaven shall be heard or feared.”

      March 27, 1798, Jefferson wrote to Mr. Patterson: “In the life time of Mr. Rittenhouse, I communicated to him the description of a mould-board of a plough, which I had constructed, and supposed to be what we might term the mould-board of least resistance. I asked not only his opinion, but that he would submit it to you also. After he had considered it he gave me his own opinion that it was demonstratively what I had supposed, and I think he said he had communicated it to you. Of that however, I am not sure, and therefore, now take the liberty of sending you a description of it, and a model which I have prepared for the Board of Agriculture of England, at their request. Mr. Strickland, one of their members, had seen the model, also the thing itself in use on my farm, and thinking favorably of it, had mentioned it to them. My purpose in troubling you with it is to ask you to examine the description rigorously, and suggest to me any corrections or alterations which you may think necessary. I would wish to have the idea go as correctly as possible out of my hands. I had sometimes thought of giving it into the Philosophical Society, but I doubted whether it was worthy of their notice, and supposed it not exactly in the line of their publications. I had therefore contemplated sending it to some of our agricultural societies, in whose way it was more particularly, when I received the request of the English board. The papers I enclose you are the latter part of a letter to Sir John Sinclair, their president. It is to go off by packett, wherefore I wish to ask the favor of you to return them with the model in the course of the present week, with any observations you will be so good as to favor me with.”

      Writing from Washington, July 15, 1808, to Mr. Sylvestre, in acknowledgment of a plow received from the Agricultural Society of the Seine (France), he adds: “I shall with great pleasure attend to the construction and transmission to the society of a plough with my mould-board. This is the only part of that useful instrument to which I have paid any particular attention. But knowing how much the perfection of the plough must depend, 1st, on the line of traction; 2d, on the direction of the share; 3d, on the angle of the wing; 4th, on the form of the mould-board; and persuaded that I shall find the three first advantages eminently exemplified in that which the society sends me, I am anxious to see combined with these a mould-board of my form, in the hope it will still advance the perfection of that machine. But for this I must ask time till I am relieved from the cares which have more right to all my time – that is to say, till next spring;” i. e. until after the expiration of his second term as President of the United States.

      The importance of any step in civilization can be understood only in its relations, antecedent causes and actual results.

      The Scientific American, which is certainly good authority in such matters, ranks Jethro Wood with Benjamin Franklin, Eli Whitney, Robert Fulton, Charles Goodyear, Samuel B. Morse, Elias Howe, and Cyrus H. McCormick, and these are certainly the great names and this a just classification. Each in his way laid the foundation on which all inventors in his respective line have built, and must continue to build, and none of them all came so near perfecting his grand idea as Mr. Wood. His now venerable daughter stated the exact truth when she remarked in a letter not designed for publication: “My father patented the shape and construction of the plow. He took the iron and shaped the plow that turns the furrow for every product of the soil in America. His plow has never been improved. It came from his hand simple and perfect, as it now is, and there is no other plow now in use.” It was not the use of cast iron that he invented, although the use of “pot metal” by him occasioned a great deal of hostility to the original Wood plow.

      Jethro Wood took out two plow patents, and those who wish to belittle his work, descant upon the first as if it were his only claim to credit. That first patent was issued in 1814. It fell far short of satisfying the patentee’s ambition. The plows made under it must have been a great improvement on any then in use, for although he abandoned it almost from the first, a great many of them were sold during the period between the first and the second patents. The second patent dates from 1819. The natal day of the modern plow may be fairly set down as September 1, 1819. The original specifications in this plow deserve to be given in full, and may well be inserted in this connection. The document was the handiwork of Mr. Wood himself, and runs thus: