The ear and the cavities of the frontal and sphenoidal bones were next opened, provided these bones were not needed for the setting up of a skeleton. Finally he took up the extremities, demonstrating the muscles of an arm and a leg on one side, and the nerves and vessels on the other. The anatomy lesson ended with the introduction of numerous vivisections. Vesalius could not entirely escape disputations, but he gave to them a close anatomic basis. Theoretical physiology was repugnant to him; for him physiology was not speculation but the sequel of anatomic research. If he at times gave free reign to his views, he indicated them as mere theories. He did not ignore pathologic conditions, but he handled them as briefly as possible. Fearing to tire his audience with too much variety, he confined his students closely to the structure of the human body. The merit of Vesalius’s public dissections, and the impression which they made upon his auditors, can be appreciated only by comparison with similar demonstrations made by his predecessors. The large and enlightened audience remained day by day for a period of three or four weeks. He says not a word about the physical and mental strain incident to such a strenuous course, in which his entire time was employed. The courses brought great financial profit to the professor. On two occasions, probably in the years 1539 and 1540, Vesalius was called from Padua to Bologna to conduct public dissections. This was a great honor, for Bologna was the city in which Mondino had revived the practical teaching of anatomy. These courses were conducted by Vesalius in a wooden building erected for that particular purpose. Here, as in Padua, the professor acted as demonstrator and lecturer, remaining in this ancient city for a period of several weeks. On the first occasion he was supplied with three human bodies and was enabled to handle the subject in grand style. At the first séance he engaged with the celebrated Professor Matthaeus Curtius, whose acquaintance he had made in 1538 while on a vacation trip, in a deep study of the question of venesection. Before a large and select assembly he demonstrated in all three bodies that Galen’s description of the vena azygos was incorrect. On the second convocation Vesalius seems to have disposed of more bodies. He reviewed Galen’s work on the joints, and by numerous specimens, which were prepared by the students, he demonstrated the difference in the ancient knowledge of the skeleton. On this occasion he undertook the complete dissection of an ape and presented its skeleton, as well as that of a man, to Professor John Andreas Albius, who held the chair of Hippocratic medicine in Bologna.