SKETCH OF JOSEPH PRESTWICH. 261 



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 condi- 

 tions and new combinations successively arose in the course of its 

 long geological history, one of constant variation in degree and inten- 

 sity 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 Tra- 

 dition of the Flood, Professor Prestwich presented various phe- 

 nomena which had come under his observation during long years of 

 geological research throughout Europe and the coasts of the Medi- 

 terranean 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 impor- 

 tant 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 publica- 

 tions, therefore, often embodied views different from the conclu- 

 sions 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 Con- 

 troverted Questions of Geology — which was published in 1875. It 

 contained six essays, the first of which was devoted to the clear defi- 

 nition of the author's attitude with respect to the doctrine of uni- 

 formity, and the others were in criticism of the astronomical theory 

 of Glacial epochs; the character, age, and make of the flint imple- 

 ments of the chalk plateau of Kent; the agency of water in volcanic 

 eruptions; the thickness and mobility of the earth's crust; and un- 

 derground 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. ISTo 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 In- 

 ternational 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." 



