Transcriber’s note: Table of Contents added by Transcriber. CONTENTS Address of the President Before the British Association 561 The Bubonic Plague 576 Gasoline Automobiles 593 Some Scientific Principles of Warfare 605 Modern Mongols 618 Religious Beliefs of the Central Eskimo 624 Mental Energy 632 Chapters on the Stars 638 Discussion and Correspondence 660 Scientific Literature 662 The Progress of Science 664 Index 669 THE POPULAR SCIENCE MONTHLY EDITED BY J. McKEEN CATTELL VOL. LVII MAY TO OCTOBER, 1900 NEW YORK AND LONDON McCLURE, PHILLIPS AND COMPANY 1900 COPYRIGHT, 1900, BY McCLURE, PHILLIPS AND COMPANY. THE POPULAR SCIENCE MONTHLY. OCTOBER, 1900. ADDRESS OF THE PRESIDENT BEFORE THE BRITISH ASSOCIATION.[A] BY SIR WILLIAM TURNER, F. R. S., UNIVERSITY OF EDINBURGH. [A] Given at Bradford on September 5, 1900. Twenty-seven years ago the British Association met in Bradford, not at that time raised to the dignity of a city. The meeting was very successful, and was attended by about two thousand persons--a forecast, let us hope, of what we may expect at the present assembly. A distinguished chemist, Prof. A. W. Williamson, presided. On this occasion the association has elected for the presidential chair one whose attention has been given to the study of an important department of biological science. His claim to occupy, however unworthily, the distinguished position in which he has been placed, rests, doubtless, on the fact that, in the midst of the engrossing duties devolving on a teacher in a great university and school of medicine, he has endeavored to contribute to the sum of knowledge of the science which he professes. It is a matter of satisfaction to feel that the success of a meeting of this kind does not rest upon the shoulders of the occupant of the presidential chair, but is due to the eminence and active coöperation of the men of science who either preside over or engage in the work of the nine or ten sections into which the association is divided, and to the energy and ability for organization displayed by the local secretaries and committees. The programme prepared by the general and local officers of the association shows that no efforts have been spared to provide an ample bill of fare, both in its scientific and social aspects. Members and associates will, I feel sure, take away from the Bradford meeting as pleasant memories as did our colleagues of the corresponding Association Française, when, in friendly collaboration at Dover last year, they testified to the common citizenship of the Universal Republic of Science. As befits a leading center of industry in the great county of York, the applications of science to the industrial arts and to agriculture will form subjects of discussion in the papers to be read at the meeting.