Thomas Jefferson Papers

To Thomas Jefferson from James Sylvanus McLean, 30 September 1802

From James Sylvanus McLean

Lancaster Coy. Septr. 30 1802


During the recess of Congress,1 when your mind is probably less occupied by the immediate concerns of government, it may perhaps not be disagreable, nor wholly unimportant, occationally to see some of the objects which investigation selects for her hours of retirement—Obscurity May have its use, and retirement is sometimes favourable to investigation; for in remote situations, physical and moral phenomena being divested of adventitious attractions, and presented to the mind in their true colours and real relations, are likely to attract its energies in proportion to their importance: at least, in this medium, many objects almost invisible in a more luminous and diversified scene, are seen so large, as compleatly to conceal some of these which with a little fomentation excite the most ardent popular attention—

Of the first of these, Steam appears to me as one of the largest and most important, and have for several years anxiously expected to hear of its extensive application to the more immediate concerns of life—Could this powerful agent be applied to agriculture?—This is believed to be possible—A great simplefication of steam enginry, so as to render it easily applicable to many purposes hitherto unattempted, is certainly practicable—This I trust would have been effected long ago, had local circumstances permitted; but in this insulated corner, not only the habits and opinions of society are unfavourable, but the entire want of mechanical assistance, and even of the most ordinary emplements of mechanism, renders the entire execution of any such thing impossible—I have been withheld however from making any communication or proposal to this effect, for several years, expecting to be able to carry my ideas into effect, notwithstanding the difficulties arrising from situation: but finding this impossible, without encountering difficulties by very considerable expence of both time and money, and which might not be sufficiently obviated in this situation, even by these means; and strongly impelled by a conviction, strengthened by every day’s attention to the subject, that important advantages might easily be derived to society from this source, I have taken the liberty on the authority of fame, to mention the subject to you, with a few observations, with a view of exciting an attention which might easily give reallety to these objects—It would give me much pleasure to involve what I possess (which I trust would be much more than sufficient) on the success of what I propose; and were I so situated as to be able to use this mode of effecting the improvement contemplated, no other would be resorted to—This however only expresses my confidence; but the grounds of this, or the facts on which it is founded, are not so easily explained, and in fact, are not of a nature perhaps, to be clearly & fully elucidated in this manner—

The principal circumstances which circumscribe the use of steam engines in their present construction, are the quantety and weight of the engine; the number of its members; and the quantety of power expended in moving these members, and keeping up a condensing vaccuum—These defects are chiefly owing to the quantety of permanently elastec fluid generated by the distillation carried on in the engine, and are also a little augmented by defective Mechanism—The very large condensing vacuum, and its attached air-pump, are greatly inconvenient, and a considerable expenditure of power is effected by this member of the engine: and when with this, the force required to move the rejecting pump against atmospheric pressure, and that for overcoming the friction of valves and plug-frames, and of all the numerous members moving in close contact, are viewed in agregate, the force remaining to be applied to use, will be found to be scarcely more than half the power generated; and the enginry requiring this great expenditure, very unweildy and complicated—These defects can be removed, it is believed, by a great simplefication of the enginry: by removing, not by adding members, and the condensing area may be brought to a very small comparative size—

The quantety of Carbon in the greese used to lubricate the moving parts of the engine, tho small, has doubtless a very hurtful effect, and ought to be removed—The affinety between metals heated to a certain degree, and Oxygene, being sufficient to draw this latter from its connection with Caloric, restrains the most useful application of steam to a pressure of about twelve pounds to the square inch: in some metals this is rather too much to preserve smoothness—This force however can conveniently be applied, and is as near to atmospheric pressure as convenience & utillety will well admit; because it is better to perform some motions of the enginry by the remaing weight of the atmosphere, than by the same additional power of steam: and when this power is wholly applied to use, except as much as is necessary to keep up a condensing vacuum, and expell the condensed steam and small portion of elastic fluid, on a very small area of real pressure, the effect produced will greatly exceed any thing hitherto exhibited or attempted, and will be effected with fewer members, and these greatly diminished in size, except only that which receives & applies the force generated—

The engine here contemplated, beside various other purposes, will be easily applied to driving heavy land carriages; to the convayance of mails; and perhaps, to pleasurable carriages; which machines, if properly constructed with divided axles and friction wheels, would not only require much less force, but would bear a considerably greater speed without inconvenience or injury, and would be equally as simple in construction, as handsome, and much more manageable—I find this construction of a single chair, with a small alteration so as to require no harness, to be much better than the common awkward and cumbersome mode—Could ploughs be driven by this engine?—And could not one man with this assistance, do the business of twenty?—This is believed to be practicable—It will certainly be attempted under every difficulty of situation, should no better easily be obtained—

I would be highly gratefied to see these things attempted under circumstances favourable to success—And tho, to be the author of so great an utillety, is worthy of ambition; and that the idea of public estimation justly acquired, and the connecting general advantages to individual convenience, are stimuli which strongly actuate my mind, I would chearfully relinquish these minutia, to one whose situation in respect to manufactures & mechanics, might render success easy—Under this impression, I shall be ready at any time, to make such communications on this subject, both chymecal and mechanical, as circumstances will permit, to any person quallefied, and desirous of receiving them: I mean, such an one as would afterwards act on his own convictions; for it should be well understood, that this is not a proposal for assistance in a pecuniary way; this would be unnecessary, could the objects be effected in this situation, by reasonable expenditure—

I shall just observe finally, that this communication, which is believed to be dictated by a desire of extending real utillety, and a conviction that much is derivable from this source, is addressed to the philosopher and philantrophist, not to the president; and is indebted for its direction principally to the sentiment, not advice, of an enlightened friend in an adjoining county—Whether it may have any effect or not, or whatever may be the opinion of the reader, the writer thinks that he is discharging a duty which he ows to society, in making some attempt to realize objects useful to society, which only local circumstances prevents him from effecting alone—Were this a matter affecting an individual only, such communication would be impertinent; but when an object is contemplated by which thousands may be benefited, it is contrary to benevolence and good citizenship, not to make such exertions for its completion, as may be within the reach of the person with whom it exists—With these observations, which are submitted to your attention with diffidence, accept the expression of my most respectful consideration

James Sylv. Mclean

RC (DLC); at head of text: “His Excellency Thomas Jefferson”; endorsed by TJ as received 7 Oct. and so recorded in SJL.

A native of York, Pennsylvania, James Sylvanus McLean received a patent in 1796 for an improvement in piano fortes. Although noted for his talents and erudition, McLean was unable to find a settled situation. He lived in several southern states, including South Carolina, where he wrote for a time for the Charleston Courier, a connection he severed after the editor attempted to steer McLean from what had been deemed his maniacal pursuit of a scheme to propel boats by steam. In April 1809, a month before spending what was almost certainly an uninvited night at Monticello, he defended himself against accusations that he had passed a forged note to a Charleston doctor. Two years later McLean began boarding in Philadelphia under an assumed name, with the intention of manufacturing soda water there. Instead, he was charged as author of a plot to extort money from Stephen Girard, a wealthy Philadelphia merchant whom McLean apparently blamed for the loss of a substantial fortune. Acquitted due to insanity in March 1812, McLean was described at the trial by his attorney, who concealed the plea from his client, as suffering from “mental wildness and incapacity,” a paranoid convinced that a conspiracy existed to block his scientific and entrepreneurial efforts. After the acquittal, reports claimed that McLean, who had included TJ among his tormentors, vowed to move to France and exert his influence over Bonaparte (List of Patents description begins A List of Patents granted by the United States from April 10, 1790, to December 31, 1836, Washington, D.C., 1872 description ends , 11; Charleston City Gazette and Daily Advertiser, 20 Apr. 1809; Alexandria Herald, 24 June 1811, 9 Mch. 1812; Report of the Trial, of James Sylvanus M’Clean, Alias J. Melville, and William L. Graham, before the Supreme Court of Pennsylvania [Philadelphia, 1812; Shaw-Shoemaker description begins Ralph R. Shaw and Richard H. Shoemaker, comps., American Bibliography: A Preliminary Checklist for 1801–1819, New York, 1958–63, 22 vols. description ends , No. 26420]; RS description begins J. Jefferson Looney and others, eds., The Papers of Thomas Jefferson: Retirement Series, Princeton, 2004–, 7 vols. description ends , 1:209).

1MS: “gongress.”

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