I write you, my dear Patsy, from the canal of Languedoc, on which I am at present sailing, as I have been for a week past, cloudless skies above, limpid waters below, and on each hand, a row of nightingales in full chorus. This delightful bird had given me a rich treat before, at the fountain of Vaucluse. After visiting the tomb of Laura at Avignon, I went to see this fountain--a noble one of itself, and rendered famous forever by the songs of Petrarch, who lived near it. I arrived there somewhat fatigued, and sat down by the fountain to repose myself. It gushes, of the size of a river, from a secluded valley of the mountain, the ruins of Petrarch's château being perched on a rock two hundred feet perpendicular above. To add to the enchantment of the scene, every tree and bush was filled with nightingales in full song. I think you told me that you had not yet noticed this bird. As you have trees in the garden of the convent, there might be nightingales in them, and this is the season of their song. Endeavor, my dear, to make yourself acquainted with the music of this bird, that when you return to your own country you may be able to estimate its merit in comparison with that of the mocking-bird. The latter has the advantage of singing through a great part of the year, whereas the nightingale sings but about five or six weeks in the spring, and a still shorter term, and with a more feeble voice, in the fall. I expect to be at Paris about the middle of next month. By that time we may begin to expect our dear Polly. It will be a circumstance of inexpressible comfort to me to have you both with me once more. The object most interesting to me for the residue of my life, will be to see you both developing daily those principles of virtue and goodness which will make you valuable to others and happy in yourselves, and acquiring those talents and that degree of science which will guard you at all times against ennui, the most dangerous poison of life. A mind always employed is always happy. This is the true secret, the grand recipe, for felicity. The idle are the only wretched. In a world which furnishes so many employments which are useful, so many which are amusing, it is our own fault if we ever know what ennui is, or if we are ever driven to the miserable resource of gaming, which corrupts our dispositions, and teaches us a habit of hostility against all mankind. We are now entering the port of Toulouse, where I quit my bark, and of course must conclude my letter. Be good and be industrious, and you will be what I shall most love in the world. Adieu, my dear child. Yours affectionately, TH. JEFFERSON.