By Prof. T. C. MENDENHALL.
JUST fifty years have passed since a small body of enthusiastic students of geology and natural history organized themselves into an association which was, for the first time in the history of this country, not local in its membership or in its purpose. As the "Association of American Geologists and Naturalists," it was intended to include any and all persons, from any and all parts of the country, who were actively engaged in the promotion of natural history studies, and who were willing to re-enforce and strengthen each other by this union. So gratifying was the success of this undertaking that after a few years of increasing prosperity under its first name, the Association wisely determined to widen the field of its operations by resolving itself into the American Association for the Advancement of Science, thus assuming to be in title what it had really been in fact, from the beginning of its existence. One of the articles of its first constitution, adopted at its first meeting, provided that it should be the duty of its president to present an address at a general session following that over which he presided. The performance of this duty can not, therefore, be easily avoided by one who has been honored by his fellow-members in being called upon to preside over the deliberations of this Association; nor can it be lightly disposed of when one realizes the importance of the occasion and recalls the long list of his distinguished predecessors, each of whom in his turn has brought to this hour at least a small measure of the work of a lifetime devoted to the interests of science.
The occasion is one which offers an opportunity and imposes an obligation. The opportunity is in many ways unique and the obligation is correspondingly great. In the delivery of this address the retiring president usually finds himself in the presence of a goodly number of intelligent people, representatives of the general public who, knowing something of the results of scientific investigation, have little idea of its methods, and whose interest in our proceedings, while entirely cordial and friendly, is often born of curiosity rather than a full appreciation of their value and importance. Mingled with them are the members and Fellows of the Association who have come to the annual gathering laden with the products of many fields which they have industriously cultivated during the year; each ready to submit his contri-
- Address of the retiring President of the American Association for the Advancement of Science. Delivered at the Indianapolis meeting, August, 1890.