Page:Popular Science Monthly Volume 52.djvu/275

Rh changes dependent upon the circumstances of the time; and that while the laws of chemistry and physics are unchangeable and as permanent as the universe itself, the exhibition of the consequences of those laws in their operation on the earth has been, as new conditions and new combinations successively arose in the course of its long geological history, one of constant variation in degree and intensity of action."

In a lecture at the Victoria Institute in 1894, and in his book, published in 1895, on Certain Phenomena belonging to the Close of the Last Geological Period and on their Bearing upon the Tradition of the Flood, Professor Prestwich presented various phenomena which had come under his observation during long years of geological research throughout Europe and the coasts of the Mediterranean as "only explicable upon the hypothesis of a widespread and short submergence of continental dimensions, followed by early re-elevation; and this hypothesis," he added, "satisfies all the important conditions of the problem."

It will be observed that Professor Prestwich occupied a kind of independent position as a geologist, identified especially with no school, but forming substantially a school by himself. His publications, therefore, often embodied views different from the conclusions which his fellow-geologists had reached; or, to paraphrase an expression of his own, while they were all generally of one opinion as to the main facts of geology, in respect to the explanation of many of those facts they held very divergent opinions. This fact gave name and character to his last book—Collected Papers on Some Controverted Questions of Geology—which was published in 1875. It contained six essays, the first of which was devoted to the clear definition of the author's attitude with respect to the doctrine of uniformity, and the others were in criticism of the astronomical theory of Glacial epochs; the character, age, and make of the flint implements of the chalk plateau of Kent; the agency of water in volcanic eruptions; the thickness and mobility of the earth's crust; and underground temperatures. While these articles were all controversial, the book, as Professor Judd well said in reviewing it, "might fairly be cited as an example of the spirit in which scientific discussions ought to be carried out. No geologist who takes up this work but will find cherished ideas reasoned against or pet notions boldly assailed. But from beginning to end of the volume he will find that no word has been written which is calculated to give pain to the most sensitive opponent." In a similar spirit he exhorted the International Geological Congress in 1888: "Let us try to avoid that error of congresses—of arrogating an infallibility which is little in accord with the progress of science."