To Thomas Jefferson from Apollos Kinsley, 22 November 1793
From Apollos Kinsley
New York Nov 22nd 1793
Sir
I have the honour to Inform you that the Machine for Makeing bricks, for which I receivd a patent, has been made, on a large scale and has been tryd and found to answer well; so far and we can jude by the tryal it has had—I have reference to that with the horizontal wheel—the other has not yet been tryd—I found it nesessary to alter the construction of the charger which forces the mortar in to the moulds. Instead of a piston fixed at the end of the plank which moves up and down I have applyd an Iron plate which moves into the box as the plank decends, and drives the mortar before it into the moulds, when the plank rises to take a second charge, the Iron plate flys out of the box horrizontally through a mortis in the plank and the plank rises without raising the mortar above the Iron plate—when the plank is raised the Iron plate moves in to the box again by means of a wait. I have mad this further alteration—that instead of moveing the charger down by a Skrew—I have loaded it with a wait which will conform to the different quantitys of mortar taken into the box—that wait is raised by a rope which winds round the perpendicular shaft—which rope is held by a hitch to the shaft, and is let loos when the wait decends. The principles on which the machine is now constructed are the same as the model in your posession though some of the move ments are efected in a different way—the reason of my troubleing your Honour with this, is, to beg the favour of you to Inform me whither those alterations can be secured to me by haveing them recorded in your Office, as improvements on my former patent, or whither it will be necssary for me to apply for a nother paten. I will if necssary send a model and specification of the present construction. I expect this Letter will be deliverd to your Honour by J. Greenleaf Esqr. who is concernd with me in the property of the Patent. If you will be so kind as to inform him what will be necssary for me to do to secure the above improvements he will Inform me. I have the honour to be Sir your most Obedient & most Humb Servt
Apollos Kinsley
PS I have never Seen the Machine constructed by Mr. Brower but have been Informed that some parts of it were much like mine—especially like some of the improvements, which were all1 made before he constructed his machine. My workmen informed me that he lost no oppertunity of examining my Machine when I was not present. I hope the Law will not permit him to reap the advantage of experriments which I have made at the expence of all my Property and much time.
RC (DNA: RG 59, MLR); addressed: “Honble Thomas Jefferson Esq Philadelphia”; endorsed by TJ as received 9 Dec. 1793 and so recorded in SJL.
Apollos Kinsley (ca. 1766–1803), a Massachusetts-born physician and inventor, attended medical classes at Columbia College from 1791 to 1793 without taking a degree. In 1795 he moved to Hartford, Connecticut, where he supervised a brickmaking operation that failed to achieve financial success, was the first American to use the cylinder printing press, and reportedly experimented with steam engines and constructed a working model of a locomotive. Kinsley subsequently returned to New York City, where John Stevens subsidized his attempts to develop an improved steam engine for pumping water (Newton C. Brainard, “Apollos Kinsely,” Connecticut Historical Society, Bulletin, xxvi [1961], 12–20; Milton H. Thomas, comp., Columbia University Officers and Alumni, 1754–1857 [New York, 1936], 180).
Kinsley’s 1 Feb. 1793 patent for his machine for makeing bricks was supplemented with another of 20 Dec. 1794 “for an improvement in tempering Mortar, & moulding the same into Bricks.” His rival, Samuel Brower of New York, had received a patent “for manufacturing brick & pantile” in August 1793 (, 8, 9; , 99, 228, 323).
1. Word interlined.