Your favor of Jan. 28. was three weeks on it’s passage to this place. I thank you for the copies of the pamphlet you have been so good as to send me. I have read it with pleasure and observe the ingenuity of the idea. having however been myself very much of a projector in mechanics, and often disappointed in my theoretical combinations, I have learnt neither to form, nor to trust any opinion on these conceptions, until confirmed by experiment. I understand from the pamphlet, and still more distinctly from your letter, that you have verified the improvement by numerous experiments, and this silences all doubt. but on this authority, I should not have expected that shifting the center of gravity of the load backward or forward from the axle would relieve the power; nor, (distinguishing between the direct line of traction from the power to the weight, and the indirect ones formed by shafts, traces Etc. and in your case by the shaft and crank) that the indirect lines of traction p.a.w. p.b.w. p.c.w. would have any advantage over the direct line p.w. into which, I had supposed, all would resolve themselves. but doubt must yield to fact, and experiment controul opinion. I sincerely wish success to your invention, as well for your own benefit as that of the public.

Since you are so kind as to wish it, I take the liberty of inclosing a trifle as a memento of my respect. it is a profile, engraved by Edwin, from an original drawn by Stewart, and deemed the best which has been taken of me. it’s chief value however is in the function it performs of gratifying your wish, and with it I pray you to accept the assurance of my great esteem and respect.

Th: Jefferson