664 JOSEPH PRESTWICU. 



versity of Sydney) and F. A. Bather (of the Geological Department . 

 British Museum), who, trained in geology under Frestwich, have since 

 gained distinction. His field excursions, however, were always highly 

 appreciated by many who found no time to nursue the science in after 

 life, 



Various papers proceeded hum rom his pen; he dealt with the much 

 discussed origin of the parallel roads of Glen Roy, and he wrote on the 

 agency of water in volcanic eruptions, believing that the water was but 

 a secondary cause, and that the phenomena were dependent on the 

 effect of secular refrigeration. He dealt also with the problem of the 

 thickness of the earth's crust, and published an elaborate x>aper on 

 underground temperatures. 



He also made a special study of the Ohesil Beach, coming to the con- 

 clusion that it was a wreck of an oi 1 and extensive raised beach, of 

 which a remnant still exists on Portland. His view concerning the 

 comparatively recent date of the Weymouth anticline has not, however, 

 proved to be sound. 



During his term of professorship, Prestwich wrote his well-known 

 work entitled "Geology — Chemical, Physical, and Stratigraphical," in 

 two volumes, published in 1886 and 1888, a work admirably illustrated. 

 Ir> the first volume he remarked that among geologists two schools 

 have arisen, "one of which adopts uniformity of action in all time, 

 while the other considers that the physical forces were more active and 

 energetic in past geological periods than at present." Advocating this 

 latter teaching he felt he should be " supplying a want by placing 

 before the student the views of a school which, until of late, has hardly 

 had its exponent in English text-books." He indeed protested on 

 many occasions against the doctrine of uniformity of action, both in kind 

 and in degree. Such, indeed, was the teaching of Ramsay in his pres- 

 idential address to the British Association at Swansea in 1880V That 

 geologist referred to the great changes, of which we have evidence in 

 comparatively late geological times, in the upheaval of mountain chains 

 and in the vicissitudes of the Glacial period; and, in regard to vol- 

 canoes, he believed that "at no period of geological history is there any 

 sign of their having played a more important part than tbey do in the 

 epoch in which we live." Ramsay based his argument on the record of 

 the rocks, and, leaving out of consideration cosmical hypotheses, he 

 concluded that, from the epoch of our oldest known rocks down to the 

 present day, " all the physical events in the history of the earth have 

 varied neither in kind nor in intensity from those of which we now have 

 experience." This conclusion may be taken to mean that any kinds of 

 physical change that have happened in the past, since the earliest rocks 

 were laid down, may happen again, and we believe that this is the real 

 view of the Uniforinitarian. Mr. Teall again, in 1893, forcibly urged 

 the claims of the Uniforinitarian school, pointing out "that denudation 

 and deposition were taking place in pre-Cambrian times, under chemi- 



