What he demanded of his students above all was that they should learn to help themselves. He set them tasks, gave them suggestions, directed their work, corrected their errors, but he wanted them to do work for themselves. His very presence was an inspiration. Both Virchow and Du Bois-Reymond speak of the power of his eye. Du Bois-Reymond says that there was in him an almost demoniac magic, and that students looked to him as the soldiers of the first Napoleon did when the great Emperor's words were in their ears--"Soldiers, the Emperor has his eye on you." Du Bois-Reymond adds that, consciously or unconsciously, every student felt the winning influence of his great personality. With all this he knew how to unbend, especially with favorite students, and many a joke from him found its way around the laboratory even during working hours. He was not one to stand on his dignity, and Virchow tells of him that even when nearly fifty he was known to race with a student down the corridor from one class-room door to another. He took up skating at the age of forty-five, and though he had not many friends and was too entirely devoted to his work to make {247} many acquaintances, it was always a source of pleasure to young men to be allowed to associate with him, and many eagerly sought the privilege. How impressive a figure Müller made in his character of teacher can be gathered best, perhaps, from a note added to Virchow's panegyric during its progress through the press, in which the pupil tells his impressions of the master: "I must confess that Müller, in his lectures and in his manner, reminded me of a Catholic priest, which might be accounted for by the impressions of his early childhood. When as the dean of the Faculty he mounted the _cathedra superior_, dressed in his official robes, and pronounced the Latin formulary of the proclamation of the doctors of medicine, with short, broken and contracted words; when he began his ordinary lectures in almost murmured syllables; or, when with religious earnestness he was discussing any of the abstruse questions of physiology, his tone and manner, his gestures and looks, all betrayed the traditional training of the Catholic priest." Virchow adds, "Müller himself was what he styled one of his greatest predecessors--perpetually a priest of nature. The religion which he served attached his pupils to him as it were by a sacred bond; and the earnest, priest-like manner of his speech and gestures completed the feeling of veneration with which everyone regarded him."