ing the tone of scientific literature, in leading to replacement of subjective by objective modes of investigation.
Darwin's work as geologist practically ended with these publications of the Beagle results. It is true that in later years he made some contributions possessing much interest, but they were merely incidental to studies in other directions; the greater part of his long life was devoted to biological problems. At the same time, his whole mode of thinking and of observing was that of the geologist, so that if one were treating of his later years the topic might well be the influence of geology upon Darwin. In his later works, one finds constantly recurring consideration of geological conditions as potent factors in biological change, while on the other hand he emphasized the influence of life as a factor in bringing about geological changes. To him nature was always one; and he, in great measure, was responsible for the broadness of view characterizing the geologists who were his contemporaries as well as for the remarkable change in attitude of the community toward scientific discussion. Nowadays, when workers are so many and knowledge is so increased, men have been forced into narrow lanes of investigation; students, perplexed by phenomena within their limited vision, too often think little and know less of what neighbors are doing. And this must continue until some important problems have been solved, at least in part, and some positive results have been obtained in many directions. Then another Darwin will come, will gather loose strands floating in the wind and will weave from them a new system, once more binding nature studies into one and providing a safe platform, whence men may start anew to fathom the unknown by means of the known.