[43] This letter, as a matter of curiosity probably, was written in a book of the bark of the paper birch, having leaves seven inches long by four wide. (Note from Randall's Jefferson.) The allusion in the following letter to the Duke of Dorset, and to his niece, the charming Lady Caroline Tufton, deserves a word of explanation. The Duke was British Minister in France during Mr. Jefferson's stay there. The two became acquainted and warm personal friends, and an intimate friendship sprang up between Martha Jefferson and Lady Caroline. On her return to America, Martha requested her father to call one of his farms by her friend's name, which he did, and a fine farm lying at the foot of Monticello bears at this day the name of Tufton. _To Martha Jefferson Randolph._--[_Extract._] Philadelphia, June 23d, 1791. I wrote to each of you once during my journey, from which I returned four days ago, having enjoyed through the whole of it very perfect health. I am in hopes the relaxation it gave me from business has freed me from the almost constant headache with which I had been persecuted during the whole winter and spring. Having been entirely clear of it while travelling, proves it to have been occasioned by the drudgery of business. I found here, on my return, your letter of May 23d, with the pleasing information that you were all in good health. I wish I could say when I shall be able to join you; but that will depend on the motions of the President, who is not yet returned to this place.