I wrote you a few days since, recommending to your notice an old acquaintance, who is bound home from Maryland to obtain holy orders. His name, Matthias Harris. Any civilities you show him, as he will be an entire stranger in London, I shall gratefully acknowledge. Only I ought to acquaint you that he has always had a strong penchant to the buying of books, and that some late misfortunes have rendered it more inconvenient to him to gratify that taste than it has been heretofore. My wife, son, and daughter desire to be respectfully remembered to you, Mrs. Strahan, and Master Billy. I am, dear sir, your obliged humble servant, B. FRANKLIN. I PHILADELPHIA, 8 December, 1752. DEAR BROTHER:-Reflecting yesterday on your desire to have a flexible catheter, a thought struck into my mind, how one might probably be made; and lest you should not readily conceive it by any description of mine, I went immediately to the silversmith's and gave directions for making one (sitting by till it was finished) that it might be ready for this post. But now it is done I have some apprehensions that it may be too large to be easy; if so a silversmith can easily make it less by twisting or turning it on a smaller wire, and putting a smaller pipe to the end, if the pipe be really necessary. This machine 'Address: "To Mr. John Franklin. Boston. Free. B. Franklin." may either be covered with small fine gut, first cleaned and soaked a night in a solution of alum and salt and water, then rubbed dry, which will preserve it longer from putrefaction; then wet again and drawn on and tied to the pipes at each end, where little hollows are made for the thread to bind in and the surface greased. Or perhaps it may be used without the gut, having only a little tallow rubbed over it, to smooth it and fill the joints. I think it is as flexible as would be expected in a thing of the kind, and I imagine will readily comply with the terms of the passage, yet has stiffness enough to be protruded; if not, the enclosed wire may be used to stiffen the hinder part of the pipe while the fore part is pushed forward, and as it proceeds the wire may be gradually withdrawn. The tube is of such a nature, that when you have occasion to withdraw it its diameter will lessen, whereby it will move more easily. It is a kind of screw and may be both withdrawn and introduced by turning. Experience is necessary for the right using of all new tools or instruments, and that will perhaps suggest some improvements to this instrument as well as better direct the manner of using it. I have read Whytt on lime-water. You desire my thoughts on what he says. But what can I say? He relates facts and experiments, and they must be allowed good, if not contradicted by other facts and experiments. May not one guess, by holding limewater some time in one's mouth, whether it is likely to injure the bladder? I know not what to advise, either as to the injec tion or the operation. I can only pray God to direct you for the best and to grant success. I am, my dear brother, yours most affectionately, B. FRANKLIN.' I found Whytt's experiments are approved and recommended by Dr. Mead. DEAR BROTHER:-With regard to our father's estate I can only so far inform you that the household stuff as sold at vendue amounted to a little more than $400 but the house and land was apprised at $2,000.2 I For the privilege of publishing this letter I am indebted to the courtesy of Dr. F. N. Otis, of New York, to whom I am also indebted for the following instructive note: "January 10, 1888. "My DEAR MR. BIGELOW:-The letter of Benjamin Franklin, written in 1752, in regard to the manufacture of a flexible catheter, seems to convey the impression that the instrument he so graphically describes was one of his own invention. I think, however, that it simply indicates his familiarity with the instrument previously in use abroad. The first mention of a flexible catheter which I can find is by Roncalus, who at first used a catheter made of a band of silver twisted in a spiral and covered with a fine skin. This he improved in 1720 by 'winding the spiral with entwisted silk, then dipped it in rosin, and afterward gave it a coat of Nuremberg plaster.' "Bernard, a jeweller (according to French authority), in 1800 (or thereabouts) sewed finely woven silk upon a staff or mandril and stiffened it with elastic gum. This is practically the method which is in use in the manufacture of catheters and other flexible urethral instruments at the present day. "Very truly yours, "F. N. OTIS." This note in the margin is in a different handwriting from the body of the letter, and was doubtless made by John, to whom it was addressed. TO WILLIAM STRAHAN PHILADELPHIA, 9 May, 1753. DEAR SIR: I have your favor of January 30th, and thank you for the civility shown, on my recommendation, to Mr. Harris. What you mention concerning the books was not at all amiss. Neither the second volume of Bower's History of the Popes, nor Delaresse's Art of Painting, nor Crito, are to be found in any of Mr. Hall's trunks. I have settled a nephew of mine in Antigua, in the place of Mr. Smith, deceased. I take him to be a very honest, industrious lad, and hope he will do well there, and in time be of some use to you as a correspondent. Please to send him a little cargo of books and stationery agreeable to the invoice below. I will send you a bill on this account perhaps per next ship. Please to send my compliments to Mrs. Strahan and Master Billy. I am, sir, your obliged humble servant, 3 ream propatria, best cut. 2 Do. pot. I Do. fine post. 500 best quills. 3 doz. British ink powder. 2 lb. wafers, some large. I doz. common Bibles. I doz. Testaments. I doz. Psalters. 2 doz. Primers. B. FRANKLIN. 1 Benjamin, the son of his sister, Mrs. Mecom. And a few of your newest and most salable books, amounting in the whole to about £25 sterling. PHILADELPHIA, 4 June, 1753. SIR: The above is a copy of mine per Reeves. This is only to request you would send me here the quarto abridgment of the Philosophical Transactions, except the first five volumes, which I have. Send me also Fielding's Proposals for Employing the Poor. In haste, I am yours, B. FRANKLIN. The five volumes of Transactions I have, are abridged by Lowthrop and Jones. All well. Mr. Hall out of town. TO WILLIAM STRAHAN PHILADELPHIA, 27 October, 1753. DEAR SIR: I have your favor of June 27th, and am quite surprised at the conduct of Mr. Harris. He is returned to Maryland, as I hear, a parson. I have now received Bower's second volume, and shall send to the Trenton Library to enquire after Crito and Delaresse. The sum was £25 to which I limited the books, etc., to be sent my nephew, Benjamin Mecom. But if you have sent to the amount of £30, it is not amiss. I am now about to establish a small printing-office in favor of another nephew, at New Haven, in the |