In physical geography, the usual school course, with its many-coloured maps, had been left far behind. Tobler, an active young man, was the principal teacher in this section. Still, even this branch had far too much positive instruction[46] for me. Particularly unpleasant to me was the commencement of the course, which began with an account of the bottom of the sea, although the pupils could have no conception of their own as to its nature or dimensions. Nevertheless the teaching aroused astonishment, and carried one involuntarily along with it through the impression made by the lightning-quickness of the answers of the children. In natural history I heard only the botany. The principal teacher, who had also prepared the plan of instruction in this subject for all the school, was Hopf, like the rest an active young man. The school course arranged and carried out by him had much that was excellent. In each separate instance--for example, the shape and position of leaves, flowers, etc.--he would first obtain all the possible varieties of form by question and answer between the class and himself, and then he would select from the results the form which was before them in nature. These lessons, which were in this way made so attractive, and whose merits spoke for themselves, showed, however, when it came to practical application, an unpractical, I had almost said, a self-contradictory aspect. (When, afterwards, in 1808, I visited Yverdon for the second time, I found to my regret neither Tobler nor Hopf there.) With the method used for the German language I could not at all bring myself into sympathy, although it has been introduced into later school books elsewhere. Here also the arbitrary and non-productive style of teaching ran strongly counter to me at every step. Singing was taught from figures.[47] Reading was taught from Pestalozzi's well-known "A.B.C."