To Charles Thomson
Philadelphia Apr. 20. 1791.
Mr. Madison and myself have been in the constant purpose, as soon as the roads should get a little smooth, to ride out some morning and pay our respects to you: the late rains have disappointed us in that respect.
The Philosophical society have appointed a committee, of which you are named, to collect materials for forming the natural history of the Hessian fly, the best means of preventing or destroying it &c. This committee meets tomorrow. I therefore send the bearer express, in hopes you will find it convenient to come. The meeting shall be fixed to any hour that may suit your convenience, if you will be so good as to notify it to me by a line by return of the bearer. I shall hope also that you will do me the favor to take your dinner with me, to which I shall endeavor to join the other three members of the committee. The object of the meeting is to plan and distribute our operations. I hope Mrs. Thompson and yourself enjoy good health. It is fortunate for you that you are scarcely within striking distance, or, in my habit of daily riding I should be troublesome to you. You will always make me happy by calling on me when you come to town, and if it be at the hour of three or a little after, I can always offer you soup, and you will generally be solus cum solo. I am with great sincerity Dear Sir Your affectionate humble servt,
RC (DLC: Charles Thomson Papers); addressed: “Charles Thomson esquire”; endorsed. PrC (DLC).
It was TJ himself who had proposed that the American Philosophical Society appoint a committee to study the Hessian fly. He was its chairman, and the other members were Dr. Benjamin S. Barton, Dr. James Hutchinson, Charles Thomson, and Dr. Caspar Wistar (APS, Procs., xxii, pt. 3 [July 1885], 193–4). For a comment on the committee’s study, see Editorial Note and group of documents concerning the northern journey of TJ and Madison, at 20 May 1791.