DEAR SIR,--Mr. Madison, who is with me, suggests the expediency of immediately taking up the case of Captain Porter, against whom you know Mr. Erskine lodged a very serious complaint, for an act of violence committed on a British seaman in the Mediterranean. While Mr. Erskine was reminded of the mass of complaints we had against his government for similar violences, he was assured that contending against such irregularities ourselves, and requiring satisfaction for them, we did not mean to follow the example, and that on Captain Porter's return, it should be properly inquired into. The sooner this is done the better; because if Great Britain settles with us satisfactorily all our subsisting differences, and should require in return, (to have an appearance of reciprocity of wrong as well as redress,) a marked condemnation of Captain Porter, it would be embarrassing were that the only obstacle to a peaceable settlement, and the more so as we cannot but disavow his act. On the contrary, if we immediately look into it, we shall be more at liberty to be moderate in the censure of it, on the very ground of British example; and the case being once passed upon, we can more easily avoid the passing on it a second time, as against a settled principle. It is therefore to put it in our power to let Captain Porter off as easily as possible, as a valuable officer whom we all wish to favor, that I suggest to you the earliest attention to the inquiry, and the promptest settlement of it. I set out to-morrow on a journey of 100 miles, and shall be absent eight or nine days. I salute you affectionately. TO MR. CRAWFORD. MONTICELLO, September 8, 1807. Thomas Jefferson presents his compliments to Mr. Crawford, and his thanks for his Observations on Quarantines, which he has read with great pleasure. Not himself a friend to quarantines, nor having confidence in their efficacy, even if they are necessary, he sees with pleasure every effort to lessen their credit. But the theory which derives all infection, and ascribes to unseen animals the effects hitherto believed to be produced by it, is as yet too new and unreceived to justify the public servants in resting thereon the public health, until time and further investigation shall have sanctioned it by a more general confidence. He salutes Mr. Crawford with great respect. TO THE SECRETARY OF THE TREASURY. MONTICELLO, September 8, 1807. DEAR SIR,--Yours of the 2d is received, and I have this day directed commissions for Bull, Hubbell, and for Benajah Nicholls of North Carolina, as Surveyor of the port of Windsor, v. Simeon Turner, resigned. This last is on the recommendation of Alston.