Front Page Titles (by Subject) TO CHARLES THOMSON 1 - The Works, vol. 5 (Correspondence 1786-1789)
The Online Library of Liberty
A project of Liberty Fund, Inc.
Search this Title:
TO CHARLES THOMSON 1 - Thomas Jefferson, The Works, vol. 5 (Correspondence 1786-1789) 
The Works of Thomas Jefferson, Federal Edition (New York and London, G.P. Putnam’s Sons, 1904-5). Vol. 5.
About Liberty Fund:
The text is in the public domain.
Fair use statement:
TO CHARLES THOMSON1
Paris, Dec. 17th, 1786.
—A dislocation of my right wrist has for three or four months past disabled me from writing except with my left hand, which was too slow and awkward to be employed but in cases of necessity. I begin to have so much use of my wrist as to be able to write, but it is slowly and in pain. I take the first moment I can, however, to acknowledge the receipt of your letters of Aug. 6, July 8, and 30. In one of these you say you have not been able to learn whether in the new mills in London, steam is the immediate mover of the machinery or raises water to move it. It is the immediate mover. The power of this agent, tho’ long known, is but now beginning to be applied to the various purposes of which it is susceptible. You observe that Whitford supposes it to have been the agent which, bursting the earth, threw it up into mountains and vallies. You ask me what I think of his book. I find in it many interesting facts brought together, and many ingenious commentaries on them, but there are great chasms in his facts, and consequently in his reasoning; these he fills up with suppositions which may be as reasonably denied as granted. A sceptical reader, therefore, like myself, is left in the lurch. I acknowledge, however, he makes more use of fact than any other writer of a theory of the earth. But I give one answer to all theorists—that is as follows: they all suppose the earth a created existence; they must suppose a Creator, then, and that he possessed power and wisdom to a great degree. As he intended the earth for the habitation of animals and vegetables, is it reasonable to suppose he made two jobs of his Creation? That he first made a chaotic lump and set it into motion, and then, waiting ages necessary to form itself—that when it had done this he stepped in a second time to create the animals and plants which were to inhabit it? As a hand of a Creator is to be called in it may as well be called in at one stage of the process as another. We may as well suppose he created the earth at once nearly in the state in which we see it—fit for the preservation of the beings he placed on it. But it is said we have a proof that he did not create it in its solid form, but in a state of fluidity, because its present shape of an oblate spheroid is precisely that which a fluid mass revolving on its axis would assume; but I suppose the same equilibrium between gravity and centrifugal force which would determine a fluid mass into the form of an oblate spheroid would determine the wise Creator of that mass if he made it in a solid state, to give it the same spherical form. A revolving fluid will continue to change its shape till it attains that in which its principles of contrary motion are balanced; for if you suppose them not balanced it will change its form. Now the balanced form is necessary for the preservation of a revolving solid. The Creator, therefore, of a revolving solid would make it an oblate spheroid, that figure alone admitting a perfect equilibrium. He would make it in that form for another reason; that is, to prevent a shifting of the axis of rotation. Had he created the earth perfectly spherical its axis might have been perpetually shifting by the influence of the other bodies of the system, and by placing the inhabitants of the earth successively under its poles it might have been depopulated; whereas being spheroidical it has but one axis on which it can revolve in equilibrio. Suppose the axis of the earth to shift 45°, then cut it into 180 slices, making every section in the plane of a circle of latitude perpendicular to the axis: every one of these slices except the equatorial one would be unbalanced, as there would be more matter on one side of its axis than on the other. There would be but one diameter drawn through such a slice which would divide it into two equal parts; on every other possible diameter the parts would hang unequal; this would produce an irregularity in the diurnal rotation. We may therefore conclude it impossible for the poles of the earth to shift if it was made spheroidically, and that it would be made spheroidal, tho’ solid to obtain this end. I use this reasoning only on the supposition that the earth has had a beginning. I am sure I shall read your conjectures on this subject with great pleasure, tho’ I bespeak before hand a right to indulge my natural incredulity and scepticism. The pain in which I write awakens me here from my reverie and obliges me to conclude with compliments to Mrs. Thomson and assurances to yourself of the esteem and affection with which I am, Dear Sir, your friend and servant.
P. S. Since writing the preceding I have had a conversation on the subject of the steam mills with the famous Boulton, to whom those of London belong, and who is here at this time. He compares the effect of steam with that of horses in the following manner: 6 horses, aided with the most advantageous combination of the mechanical powers hitherto tried will grind 6 bushels of flour in an hour, at the end of which time they are all in a foam and must rest. They can work thus 6 horses in the 24, grinding 36 bushels of flour which is six to each horse for the 24 hours. His steam mill in London consumes 120 bushels of coal in 24 hours, turns 10 prs of stones which grind 8 bushels of flour an hour each, which is 1920 bushels in the 24 hours. This makes a peck and a half of coal perform exactly as much as a horse in one day can perform.
[1 ]From Collections of the N. Y. Historical Society for 1878, p. 230.