I have naturally kept in mind the needs of my own students, past and present, yet I believe these pages may be useful to students of natural science as well as to those who concern themselves with the humanities. We live in an age of narrow specialization--at all events in America. Agassiz was a specialist, but not a 'narrow' one. His example should therefore be salutary to those persons, on the one hand, who think that a man can have general culture without knowing some one thing from the bottom up, and, on the other, to those who immerse themselves and their pupils blindly in special investigation, without thought of the _prima philosophia_ that gives life and meaning to all particular knowledge. There can be no doubt that science and scholarship in this country are suffering from a lack of sympathy and contact between the devotees of the several branches, and for want of definite efforts to bridge the gaps between various disciplines wherever this is possible. It may not often be possible until men of science generally again take up the study of Plato and Aristotle, or at least busy themselves, as did Agassiz, with some comprehensive modern philosopher like Schelling. But it should not be very hard for those who are engaged in the biological sciences and those who are given to literary pursuits to realize that they are alike interested in the manifestations of one and the same thing, the principle of life. In Agassiz himself the vitality of his studies and the vitality of the man are easily identified. In conclusion I must thank the publishers, Houghton Mifflin Company, for the use of selections from the copyright books of Mrs. Agassiz and Professor Shaler; these and all other obligations are, I trust, indicated in the proper places by footnotes. I owe a special debt of gratitude to Professor Burt G. Wilder for his interest and help throughout. LANE COOPER CORNELL UNIVERSITY, April 7, 1917. CONTENTS I. INTRODUCTORY NOTE II. AGASSIZ AT NEUCHATEL III. AGASSIZ AT HARVARD IV. HOW AGASSIZ TAUGHT PROFESSOR SHALER V. HOW AGASSIZ TAUGHT PROFESSOR VERRILL VI. HOW AGASSIZ TAUGHT PROFESSOR WILDER VII. How AGASSIZ TAUGHT PROFESSOR SCUDDER VIII. THE DEATH OF AGASSIZ--HIS PERSONALITY IX. OBITER DICTA BY AGASSIZ X. PASSAGES FOR COMPARISON WITH THE METHOD OF AGASSIZ I INTRODUCTORY NOTE When the question was put to Agassiz, 'What do you regard as your greatest work?' he replied: 'I have taught men to observe.' And in the preamble to his will he described himself in three words as 'Louis Agassiz, Teacher.'