a success in this direction with which in this country we can only compare Liebig's successful instruction in Giessen.
The power of attracting young men and interesting them in scientific questions was early noticeable in Ludwig. At Marburg, already in the year 1842, we find him working in connection with his scholars, or, as he always designated them, "his young friends," among whom some, such as C. Eckhard and Ad. Fick, afterward became his physiological colleagues. In the same way, during his six years' stay at Zurich, he gathered about him as fellow-workers in his researches all the stronger elements there. His power of attraction soon spread beyond the limits of the university, and later in Vienna, and finally here in Leipsic increased in a nearly geometrical rate of progression. The number of young men from all over the world whom Ludwig has guided to independent investigation has increased in the course of years to several hundred, and we see on the list some of the first names of our modern scientific world. Yet all Ludwig's pupils have all their lives looked up to him with deepest gratitude and affection, and have recognized how much they profited just from him in the line of intellectual education. "I owe Ludwig," a prominent investigator wrote me recently, "my scientific conscience, and instinctive repugnance to any bungling."
In trying to account for Ludwig's wonderful gift for teaching, I find the first main condition in his highly ideal spirit; the second, however, in his deep love on the one hand for investigating and on the other for aspiring youth. Only he who feels deeply can attach others to himself for any length of time. When Ludwig spoke of his pupils as his young friends this was no mere figure of speech; he was in reality personally interested in them, and even after many years had passed, still followed their later career with all the sympathy of a true friend. When he gave the young men who came to him scientific work to do, and with unselfish devotion taught them the first principles of physiological thought, interrogation, and method, his power of combining the qualities of teacher and fellow-worker was unsurpassed. He knew, moreover, how to deal with each one according to his particular nature, and the large field of work he controlled made it possible for him to give suitable work to pupils of the most varied talents and training. One he placed in the chemical laboratory, another before the microscope; to sensitively organized natures he gave delicate experiments to do, and even if a clumsy worker applied to Ludwig, he was not disappointed, but was placed in the care of that careful and experienced assistant, Salvenmoser. Even if such a pupil was never able to do independent work, he at least had the opportunity of learning by his own observation the great importance of order and precision in all scientific undertakings.
