I am much obliged to you for your kind letter which let me know of your movements. I had not heard of them since I saw the Fergusons.... We have been here since parliament rose, as I am not yet at all equal to going to Brougham. My health is now quite restored; but I shall not soon--nor in all probability ever--recover the losses I have been afflicted with. I passed the greater part of last winter in Provence, expecting some relief from change of scene and from the fine climate; but I came back fully worse than when I went. In fact, I did wrong in struggling at first, which I did to be able to meet parliament in January last. If I had yielded at once, I would have been better. I hope and trust they sent you a book I published two years ago; I mean the "Dissertations," of which one is on the "Principia," and designed to try how far it may be taught to persons having but a very moderate stock of mathematics; also, if possible, to keep alive the _true taste_ (as I reckon it) in mathematics, which modern analysis has a little broken in upon. Assuming you to have got the book, I must mention that there are some intolerable errors of the press left, such as.... Excuse my troubling you with these errata, and impute it to my wish that you should not suppose me to have written the nonsense which these pages seem to prove. By the way, it is a curious proof of university prejudice, that though the Cambridge men admit my analysis of the "Principia" to be unexceptionable, and to be well calculated for teaching the work, yet, _not being by a Cambridge man_, it cannot be used! They are far more liberal at Paris, where they only are waiting for my analysis of the second book; but I put off finishing it, as I do still more my account of the "Mecanique Celeste." The latter I have almost abandoned in despair after nearly finishing it; I find so much that cannot be explained elementarily, or anything near it. So that my account to be complete would be nearly as hard reading as yours, and not 1000th part as good.... I greatly envy you Siena; I never was there above a day, and always desired to stay longer. The language is, as you say, a real charm; but I was not aware of the preservation in which you describe the older manners to be. I fear I shall not be able to visit Provence, as I should have wished this winter ... but my plans are not quite fixed. The judicial business in Parliament and the Privy Council will also make my going abroad after January difficult. I don't write you any news, nor is there any but what you see in the papers. The Tory restoration approaches very steadily, tho' not very rapidly; and I only hope that the Whigs, having contrived to destroy the Liberal party in the country--I fear past all hope of recovery--may not have a war abroad also to mourn for....