Reviews. 



The Great Ice Age. By Professor James Geikie. Third edition. 

 London: Edward Stanford, 1894, pp. xxviii + 850. xvii 

 plates. 



The progress of glacial geology has been so great during the last 

 few years that a new edition of this classic work is most welcome. 

 Much the larger part of the volume has been rewritten. Even those 

 parts which are only revised are so modified that they read as if now 

 written for the first time. Apart from the alterations which the studies 

 of recent years have made necessary, the general scope of the volume 

 is somewhat changed. In the present edition, the glacial phenomena 

 of the continent of Europe have received much fuller and much more 

 systematic treatment than in the preceding. The glacial phenomena 

 of Asia, Africa, Australia and South America also come in for their 

 share of attention. The chapters which deal with the glacial phe- 

 nomena of North America (52 pages) were contributed by Professor 

 Chamberlin, and suggest much that is new in the way of classification 

 and correlation. Another important change is the transfer of the dis- 

 cussion of the causes of the glacial period to the end of the volume. 

 This arrangement seems to make this chapter much less than heretofore 

 an organic part of the volume, and it is distinctly pointed out that the 

 general facts and relations set forth in the rest of the volume are not 

 dependent on any particular theory of glacial climate. Many of the 

 minor changes of the volume are significant, and not the least point 

 of significance is the fact that they are very generally brought into har- 

 mony with the results of recent research in our own country. 



By way of illustration it may be mentioned that kames and asar are 

 now sharply distinguished from each other, and that the discussion con- 

 cerning their origin is somewhat changed. It is interesting to note that 

 Professor Geikie believes the asar to be, for the most part, the products 

 of subglacial, not of superglacial streams. In connection with kames 

 some interesting facts concerning their distribution and relations are 

 indicated. In Scotland they are said to be especially abundant " oppo- 



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