"The lecture concludes with a demonstration showing that a free body in hyperbolic non Euclidean space may be so fashioned as in real time to carry out the actual motions of the top. The form of such a body and the forces to actuate it are specified. Klein lays great stress on the beauty of this generalization. ...The full geometry of this case is not carried out in these lectures, however, and Klein regrets that the development of thes has recently fallen into abeyance."

“Biographical Memoir of Carl Barus 1856-1935 by, presented to the at the Autumn meeting.”

“ew important steps in dynamical geology will be made until the methods for the accurate measurement of high temperatures and high pressures have not only been perfected but rendered easily available. On the basis of this conviction the present memoir on high temperatures has been prepared... f the investigation be of any fullness, it is almost essential that the observer master the component parts of his research separately; and not until he has satisfactorily done this can he apply them conjointly.”

“In even greater measure is this true of the top. The top has been everybody's toy and must, therefore, at one time or another have piqued everybody's curiosity. Lagrange, Poinsot, Jacobi, not to mention other great names, have in turn paid their tribute; yet the top may be set spinning to-day, unhampered by a completed theory to account for its evolutions.”

“he rooms which had been placed at my disposal by the American Museum of New York became temporarily unavailable. ...e determined to rent a house in New Haven, Conn., and thither the laboratory was removed in November, 1882. ...he city offered excellent library and other facilities for scientific work, such as can be met only in the immediate vicinity of a large university . ...The work in New Haven was not satisfactorily completed. In July, 1883, with the appointment of Prof. F. W. Clarke as chief chemist of the Geological Survey, our laboratory was officially connected with the chemical laboratory. Conformably with the further decision of the Director, by which the divers laboratories of the Geological Survey were united in one central laboratory in Washington, it was again necessary to change our basis of operations, this time... from New Haven to Washington. In the quarters assigned to us in the U. S. National Museum, temperature work on so large a scale... appeared impracticable, and it was therefore abandoned. ...In place of the dangerous and cumbersome apparatus of the former laboratory, the endeavor is made to reduce all apparatus to the smallest dimensions compatible with reasonable accuracy of measurement.”

“Among recent contributions we may refer in particular to Professor A. G. Greenhill's noteworthy papers... when one remembers that these complex curves reach only especially simple cases of motion, one may get some notion of the difficulty of the problem involved.”

“Mathematicians will do well to observe that a reasonable acquaintance with theoretical physics at its present stage of development, to mention only such broad subjects as electricity, elastics, hydrodynamics, etc., is as much as most of us can keep permanently assimilated. It should also be remembered that the step from the formal elegance of theory to the brute arithmetic of the special case is always humiliating, and that this labor usually falls to the lot of the physicist.”