Thomas Jefferson Papers
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Thomas Jefferson to Robert Patterson, 27 December 1812

To Robert Patterson

Monticello Dec. 27. 12.

Dear Sir

After an absence of five weeks at a distant possession of mine to which I pay such visits three or four times a year, I find here your favor of Nov. 30. I am very thankful to you for the description of Redhefer’s machine. I had never before been able to form an idea what his principle of deception was. he is the first of the inventors of perpetual motion, within my knolege, who has had the cunning to put his visitors on a false pursuit, by amusing them with a sham machinery, whose loose & vibratory motion might impose on them the belief that it is the real source of the motion they see. to this device he is indebted for a more extensive delusion than I have before witnessed on this point. we are full of it as far as this state, & I know not how much farther. in Richmond they have done me the honor to quote me as having said that it was a possible thing. a poor Frenchman who called on me the other day with another invention of perpetual motion, assured me that Dr Franklin, many years ago expressed his opinion to him that it was not impossible. without entering into contest on this abuse of the Doctor’s name, I gave him the answer I had given to others before, that the almighty himself could not construct a machine of perpetual motion, while the laws exist which he has prescribed for the government of matter in our system: that the equilibrium established by him between cause & effect must be suspended to effect that purpose. but Redhefer seems to be reaping a rich harvest from the public deception. the office of Science is to instruct the ignorant. would it be unworthy of some one of it’s votaries who witness this deception to give a popular demonstration of the insufficiency of the ostensible machinery, & of course of the necessary existence of some hidden mover? and who could do it with more effect on the public mind than yourself?

I recieved at the same time the Abbé Rochon’s pamphlets & book on his application of the double refraction of the Iceland Spath to the measure of small angles. I was intimate with him in France, and had recieved there, in many conversations, explanations of what is contained in these sheets. I possess too one of his lunettes, which he had given to Doctor Franklin and which came to me thro’ mr Hopkinson. you are therefore probably acquainted with it. the graduated bar on each side is 12. I. long, the one extending to 37.′ of angle, the other to 3438 diameters in distance of the object viewed. on so large a scale of graduation, a Nonius might distinctly enough subdivide the divisions of 10″ to 10.1 each; which is certainly a great degree of precision. but not possessing the common micrometer of two semi-lenses, I am not able to judge of their comparative merit.

With respect to the time piece, I would rather have it ensured, on account of the dangers of the season as well as of the enemy. mr Gibson of Richmond, to whom it is to be addressed, will pay all charges, and as soon as mr Voight sends me his bill, I will have the amount remitted. the package should be water-tight, as it will be long exposed on our river in a boat open to rain. perhaps it would2 not be amiss to roll the instrument up in what are called Dutch or striped blankets, which will be afterwards worth here what they cost there.3 with this precaution, I once before recieved a clock from Philadelphia in perfect good order. at all times & affectionately yours

Th: Jefferson

RC (CtY: Franklin Collection); addressed: “Doctr Robert Patterson Philadelphia”; franked; postmarked Milton, 30 Dec.; endorsed by Patterson as received 2 Jan. 1813. PoC (DLC).

The poor frenchman may have been Charles Gobert, who was related by marriage to James Monroe. A civil engineer living primarily in New York and Philadelphia, in July 1813 Gobert offered to bet any amount from $5,000 to $100,000 that Charles Redheffer’s perpetual-motion machine worked. Later that year Redheffer allegedly made off with $20,000 in notes from Gobert (Baltimore Weekly Register, 21 Aug., 2 Oct. 1813). Early in the War of 1812 Monroe helped Gobert obtain a contract to deliver musket balls of a certain density, but he failed to honor this agreement. Gobert was very likely the Carlos Goberto de Ceta who unsuccessfully tried to corner the Cuban ice market about 1815–16 (Public Defaulters Brought to Light. in a Series of Letters addressed to the People of the United States, by a Native of Virginia [New York, 1822], 5–6; Carl Seaburg and Stanley Paterson, The Ice King: Frederic Tudor and His Circle, ed. Alan Seaburg [2003], 56–8).

At some point Gobert transmitted to TJ a copy of his proposal entitled “THE WATER-BOAT, a New Invention, Of the greatest importance to the Agricultural and Commercial World,” describing his invention of a gravity-powered “quadruple balance-lever” as the engine for a paddleboat; soliciting funds for obtaining a patent and building and operating a working model and six full-size paddleboats; seeking a gentleman or his affiliated “rich house or company” to provide capital, with an initial, refundable outlay of $4,000 to be followed over the next forty months by an additional $200,000; promising the investor half of the patent right, half of the proceeds from sales of usage rights, and half of the earnings from boats in service; suggesting that profits would mount so quickly that only $100,000 might be needed from the investor’s own funds; recounting his other inventions, including a “new species of harbour-defence” and a “particular key” for moving stone piers; and explaining that his need for capital stems from thirteen months of imprisonment, 1810–11, “in a dungeon of the fortress of St. Marcos, in St. Augustine,” where Jose Gregorio Quintano, a corrupt judge, stole all his property (pamphlet in DLC: TJ Papers, 196:34849–50; dated New York, 1 June 1812; signed by Gobert, with blanks filled in and printed addendum initialed by Gobert; at foot of first page: “To his Excellency Thomas Jefferson”). Gobert received no such patent.

In an 11 Nov. 1784 letter to David Rittenhouse, TJ reported gazing into a telescope that Alexis Marie Rochon had fitted with lenses made from the iceland spath, a type of crystal (OED description begins James A. H. Murray, J. A. Simpson, E. S. C. Weiner, and others, eds., The Oxford English Dictionary, 2d ed., 1989, 20 vols. description ends ), and seeing “at the same instant an object on the banks of the Seine and a house half a mile further back with equal precision, the intermediate objects being dim as not at a proper distance for either focus.” He noted further that Rochon “thinks it will be more accurate than those hitherto known” (PTJ description begins Julian P. Boyd, Charles T. Cullen, John Catanzariti, Barbara B. Oberg, and others, eds., The Papers of Thomas Jefferson, 1950– , 34 vols. description ends , 7:517). A nonius is a quadrant engraved with a series of concentric arcs that facilitate the measurement of angles, altitudes, and heights (OED description begins James A. H. Murray, J. A. Simpson, E. S. C. Weiner, and others, eds., The Oxford English Dictionary, 2d ed., 1989, 20 vols. description ends ).

1Number reworked from “100.”

2TJ enhanced this word in PoC as “might.”

3Preceding ten words canceled in RC by TJ or a later reader after removal of document from polygraph.

Index Entries

  • boats; design of search
  • clocks; TJ’s astronomical case clock search
  • Franklin, Benjamin; and lunette search
  • Gibson, Patrick; and shipments to TJ search
  • Gibson & Jefferson (Richmond firm); and household articles acquired by TJ search
  • Gobert, Charles; and paddleboat search
  • Gobert, Charles; and perpetual-motion machine search
  • Hopkinson, Francis; and lunette search
  • inventions; perpetual-motion machine search
  • Jefferson, Thomas; Opinions on; perpetual-motion machines search
  • lunettes search
  • Mémoire sur le micromètre de cristal de Roche (A. M. Rochon) search
  • Patterson, Robert; and astronomical case clock search
  • Patterson, Robert; and perpetual-motion machine search
  • Patterson, Robert; letters to search
  • perpetual-motion machines; of C. Redheffer search
  • perpetual-motion machines; TJ on search
  • Redheffer, Charles; perpetual-motion machine of search
  • Rittenhouse, David; and A. M. Rochon’s telescope search
  • Rochon, Alexis Marie; Mémoire sur le micromètre de cristal de Roche search
  • Rochon, Alexis Marie; telescopes of search
  • scientific instruments; lunettes search
  • scientific instruments; telescopes search
  • subscriptions, non-publication; to support business ventures search
  • telescopes; A. M. Rochon’s search
  • Voigt, Thomas; and TJ’s astronomical case clock search