Your esteemed favour, accompanying the German pamphlet by Angermann, on the preservation of Timber, came to hand in due time. I am highly indebted to you for the consideration, and interest which you take in the work which I am preparing for press, and I only regret that the merits of Angermann’s tract did not render it more worthy of the trouble it has occasioned you. I do not understand German, but my friend Dr Seybert of this City is master of that language, and without any possible exception, the best chemist in America theoretical and practical. He was polite enough to read the work, by Angermann, and to give me his opinion of it, which amounted to this, that as not a single prooff was adduced in support of the efficacy of the preservative compositions recommended, and as some of the articles decomposed others and left one alone to act on the wood, he did not think the use of all the articles necessary. The active ingredient appeared to be common salt! the efficacy of which is well known. But in my opinion the best remedy to preserve timber is to use it after being well seasoned, and to provide for the due ventilation of it, when necessarily exposed to moisture.—I shall touch on this subject under the article “House.” In the second vol: under the article “Dry rot” some remarks are made by Dr Willich, and also under the head “Timber.”—

I have lately been reading your description of the mould board of a plough, and prevailed upon an ingenious pattern maker to attend to the explanation of the various parts of the model blocks, in the possession of the Phil: Soc: he understood them perfectly, and has agreed with me to make one, but I wish if possible to1 have the plates Cast in order that they may be generally used, and their merits fairly ascertained. In reading your explanation something occurred which required still further explanation from you, and I shall esteem myself much indebted to you, for the necessary illustration.—you say p 319. “In practice I have found some other modifications of it advantageous.”—again p 320 “But now satisfied, that for a furrow of nine by six inches, the dimensions I have stated are the best, I propose to have the mould board made of Cast iron.”—   Permit me to ask, what are the circumstances, requiring the “modifications” and by what rule can we ascertain the proper thickness of the mould plate when Cast?—Have any been cast which meet your full approbation, and can I obtain one?—As I deem the most2 proper form of a plough of infinite Consequence, I am exceedingly anxious to see an experiment tried with3 one having a plate of your particular form, and also to gratify myself by introducing your pattern into Pennsya; for, from all the inquiries I have made, I cannot learn that a single mould board has been made agreeably to the plan you recommend. Our Philosophers here are not farmers, and our farmers never heard of your mould board. Thus it is, that this seperation of science from practice, proves so injurious to the progress of improvement. I offered to make an attempt to unite both, but was prevented, and by those who ought to have encouraged my zeal.—

The patent mould plate of Mr Smith of Bucks County, has attained great Credit in that part of the Country, on account of the ease with which it works; I have seen the plough made under his direction, but not at work. When I get one of your construction I am determined to try it along side of Smith’s, and to procure the English4 contrivance of a screw or spring steel yard, fixed so as to tell the precise force with which both ploughs5 draw.—

I am the more anxious respecting the detail of the principles, and of the precise6 dimensions of your plate, because I am desirous to mention it in my work, and I should be very happy in recommending it from my own experience to our farmers.—

Wishing you all health and happiness I remain yours Sincerely