Terrible German roads. Missed J. W. A. Pfaff in Erlangen, where university is on vacation. Describes caves of Muggendorff near Bayreuth. Visited Mr. Lindeman and J. F. Encke in Gotha. [Letter continued 30 Sept. in Göttingen:] Found letter from Caroline Herschel with enclosure from Charles Babbage. Hopes to visit K. L. Harding and J. F. Blumenbach in Göttingen.