Nothing would have seemed more natural than to leave Pasteur to his experiments. But his appointment to some definite post could no longer be deferred, in spite of Balard’s tumultuous activity. The end of the summer vacation was near, there was a vacancy: Pasteur was made a Professor of Physics at the Dijon Lycée. The Minister of Public Instruction consented to allow him to postpone his departure until the beginning of November, in order to let him finish some work begun under the eye of Biot, who thought and dreamt of nothing but these new investigations. During thirty years Biot had studied the phenomena of rotatory polarization. He had called the attention of chemists to these phenomena, but his call had been unheeded. Continuing his solitary labour, he had--in experimenting on cases both simple and complex--studied this molecular rotatory power, without suspecting that this power bore a definite relation to the hemihedral form of some crystals. And now that the old man was a witness of a triumphant sequel to his own researches, now that he had the joy of seeing a young man with a thoughtful mind and an enthusiastic heart working with him, now that the hope of this daily collaboration shed a last ray on the close of his life, Pasteur’s departure for Dijon came as a real blow. “If at least,” he said, “they were sending you to a Faculty!” He turned his wrath on to the Government officials. “They don’t seem to realize that such labours stand above everything else! If they only knew it, two or three such treatises might bring a man straight to the Institut!” Nevertheless Pasteur had to go. M. Pouillet gave him a letter for a former Polytechnician,[18] now a civil engineer at Dijon, a M. Parandier, in which he wrote-- “M. Pasteur is a most distinguished young chemist. He has just completed some very remarkable work, and I hope it will not be long before he is sent to a first-class Faculty. I need add nothing else about him; I know no more honest, industrious, or capable young man. Help him as much as you can at Dijon; you will not regret it.” Those first weeks away from his masters and from his beloved pursuits seemed very hard to Pasteur. But he was anxious to prove himself a good teacher. This duty appeared to him to be a noble ideal, and to involve a wide responsibility. He felt none of the self satisfaction which is sometimes a source of strength to some minds conscious of their superiority to others. He did not even do himself the justice of feeling that he was absolutely sure of his subject. He wrote to Chappuis (November 20, 1848): “I find that preparing my lessons takes up a great deal of time. It is only when I have prepared a lesson very carefully that I succeed in making it very clear and capable of compelling attention. If I neglect it at all I lecture badly and become unintelligible.”