During this period Goethe entered upon the scientific investigations which were to occupy many of the best hours of his life. Almost from boyhood he had had a strong inclination for the study of science. At Leipsic he attended lectures on physics and medicine, and at Strasburg, as we have seen, he gave some attention to various branches of biology. Now he devoted himself to science with an enthusiasm not less fervent than that with which he had devoted himself to literature. He began with mineralogy, to which he was led by his labours in connection with the Ilmenau mines, and mineralogy soon made it necessary for him to turn his thoughts to geology. Afterwards he occupied himself chiefly with osteology and botany. For his investigations in all these subjects he had considerable advantages. The collections at the University of Jena were of course at his disposal, and the scientific professors were only too glad to have a chance of giving him what aid they could. In botany he was able to carry on long series of researches in his garden, and in the forests of the duchy, which he had frequently to visit as an administrator. He took up the study of science in a serious spirit, and, as the results proved, he had a high capacity for it. He was a careful and most exact observer, and his imagination, so far from standing in his way, was the power to which he owed the greatest and most fertile of his ideas. It was in osteology that he made his first important discovery. In the study of this branch of anatomy he was interested mainly in the points of comparison between the human skeleton and the skeletons of other vertebrates. It was generally held that the intermaxillary bone, which is found in the upper jaw of some animals, is wanting in man, and this was regarded as a proof of the doctrine that the physical nature of man is vitally distinguished from that of other living creatures. On March 27, 1784, while examining various bones with his friend Professor Loder, of the University of Jena, Goethe was greatly surprised to discover what he believed to be the intermaxillary bone in a human jaw. He lost no time in comparing it with the various forms assumed by the bone in different species of animals, and the more widely the comparison was extended the more sure he became that he was right. The results of his researches he set forth in an essay, illustrated by drawings. This essay, which is a model of lucid statement, was translated into Latin, and submitted to several men of science. It was not, however, published until about thirty years afterwards.