A letter to his brother, of the 29th of May, just after his return to Munich, gives a retrospect of the Viennese visit, including the personal details which he had hesitated to write to his father. They are important as showing the position he already, at twenty-three years of age, held among scientific men. "Everything," he says, "was open to me as a foreigner, and to my great surprise I was received as an associate already known. Was it not gratifying to go to Vienna with no recommendation whatever, and to be welcomed and sought by all the scientific men, and afterwards presented and introduced everywhere? In the Museum, not only were the rooms opened for me when I pleased, but also the cases, and even the jars, so that I could take out whatever I needed for examination. At the hospital several professors carried their kindness so far, as to invite me to accompany them in their private visits. You may fancy whether I profited by all this, and how many things I saw." After some account of his business arrangements with Cotta, he adds "Meantime, be at ease about me. I have strings enough to my bow, and need not feel anxious about the future. What troubles me is that the thing I most desire seems to me, at least for the present, farthest from my reach,--namely, the direction of a great Museum. When I have finished with Cotta I shall begin to pack my effects, and shall hope to turn my face homeward somewhere about the end of August. I can hardly leave earlier, because, for the sake of practice, I have begun to deliver zoological lectures, open to all who like to attend, and I want to complete the course before my departure. I lecture without even an outline or headings before me, but this requires preparation. You see I do not lose my time." The next home letter announces an important change in the family affairs. His father had been called from his parish at Orbe to that of Concise, a small town situated on the south-western shore of the Lake of Neuchatel. FROM HIS MOTHER. ORBE, July, 1830.