I recieved in due time your friendly letter inclosing two pamphlets. I have deferred acknoleging them till I could have time to read them. that time should be scarce here will seem odd to you. but mine, from an early breakfast to a late dinner is given to my farms, & from dinner to early bedtime to society or light reading. I have read that on animal life with very great delight. a great number of facts, which laid in piles in my mind, are now reduced into order, enlarged by many additional ones, and the whole beautifully arranged. to mention the particulars I approve, would be to copy the book. I shall therefore criticise the only fact I dispute. you think that the storm of stimuli, agitating the system from 15. to 35. ceasing at that age, is succeeded & supplied by that of ambition; and I know that that passion has been frequently considered as the vice of age. my observations on myself & those around me contradict this fact, and make1 ambition end where you suppose it to begin. I believe it to be a passion taking it’s root in the full tide of life, & withering with it’s ebb. till the age of 15. it’s circle is small & little more than domestic. at that age it begins to look at public men & public things, is in it’s akmé by 25. and at 35. we already sigh for2 tranquility as the supreme good, & make this our principal object through declining life. men may & do continue in public life to very late periods,3 from avarice, from the vicious passions of party, from virtuous wishes to promote the public good or public liberty, but not from a passion for pre-eminence in the eyes of their fellow citizens. the enthusiasm which renders that delicious, cools down with the enthusiasm of other pleasures. I well remember that at 38. I retired into port perfectly sated with public life, and determined no more to embark in it. that that purpose was yielded, is accounted for with perfect satisfaction to my own mind from circumstances entirely unconnected with ambition. I think I have remarked the same rise progress & decline in that passion among my acquaintances & companions in public life generally, & have therefore long ago disbelieved the observation that ambition is the passion of old age.

Do we dream more in age than in infancy? I suspect not. dreams seem to be the consequence of some embarrasment in the animal system. a supper, or the undigested dregs of a dinner interrupt our sleep with dreams. but when all the functions of life are perfectly performed, sound sleep seems to be the consequence in every age.

The origin of the yellow fever being a vexata questio among the medical gentlemen, it is not for the unlearned to form an opinion on it. I believe it will be found that the close & solid method of building up cities in the cloudy climates of Europe4 must not be pursued under our clear sky. the quantity of our sunshine imposes a different law on us. all towns in America should be laid off on the plan of the chequer board, the white squares remaining unbuilt & in trees. every house would then front a square of trees: and the accidents of fire as well as disease better guarded against. from the accounts in the newspapers we may hope the visitation of your city will be more light this year. but I expect that this calamity will prevent the growth of cities beyond a very moderate size. perhaps manners will not be the worse for that. were such a city as Philadelphia offered to be planted in this state, I would accept it on no condition but that of breaking it up into squares & planting one in the center of each county. my best wishes attend yourself personally and your family, and that you may take a prudent care of yourself & them. Adieu affectionately