496 Recent Literature. [June, 



To the general student the closing third of the book will com- 

 mend itself. The writer successfully applies the doctrine of con- 

 tinuity to volcanism and volcanic rocks. He claims that the 

 granites formed in Tertiary times present no essential points of 

 difference from those which originated in the earlier periods, and 

 that the same materials may, under different conditions " assume 

 either the characters of granite on the one hand, or of pumice on 

 the other." Professor Judd assumes that " the careful considera- 

 tion of all the facts of the case leads to the conclusion that when 

 pumice, obsidian and rhyolite are now being ejected at the sur- 

 face, the materials which form their substances are, at various 

 depths in the earth's interior, slowly consolidating in the form of 

 quartz-felsite, granite-porphyry and granite," and after farther dis- 

 cussion, he concludes " that the manifestations of the subterranean 

 forces in the past agree precisely in their nature and in their pro- 

 ducts with those taking place around us at the present time." We 

 are then led to the subject of the formation of mountain chains, 

 which are happily termed " cicatrised mounds in the earth's solid 

 crust." He then epitomises the leading events in the formation 

 of mountain chains. 



" A line of weakness first betrays itself at a certain part of the 

 earth's surface by fissures, from which volcanic outbursts take 

 place, and thus the position of the future mountain chain is deter- 

 mined. Next subsidence during many millions of years permits 

 of the accumulation of the raw materials out of which the 

 mountain range is to be formed; subsequent earth-movements 

 cause these raw materials to be elaborated into the hardest and 

 most crystalline rock-masses, and place them in elevated and 

 favorable positions ; and lastly, denudation sculptures from these 

 hardened rock-masses all the varied mountain forms. Thus the 

 work of mountain making is not, as was formerly supposed by 

 geologists, the result of a simple upheaving force, but is the out- 

 come of a long and complicated series of operations." 



What volcanoes teach us concerning the nature of the earth s 

 interior is given in a clear, interesting way. The " crust of the 

 earth " is, as geology now shows, only that part of a solid globe 

 accessible to examination, and the interior may consist of mat- 

 erials similar to those found in meteorites, while the volcanic 

 phenomena witnessed on our earth may be identical in nature 

 with the great movements in other worlds than ours." 



Brunton's Bible and Science. 1 — The author of this excellent 

 book makes a very successful attempt to reason with those who 

 " ; of evolution " with horror mingled with fear. 



uai.t 



gives a brief, popular and very readable sketch of some °f the , 

 i on which the doctrine is founded, and shows " that instead 01 



