368 . Dr. J. Croll on the Physical Theory 



Palaeontology are as much opposed to the conclusion as are 

 the principles of Physics. 



On this point I may quote the evidence of a geologist who, 

 more than any other, has devoted special attention to all points 

 relating to Glacial and Interglacial periods. Prof. J. Geikie, 

 after devoting upwards of 500 pages of his ' Prehistoric 

 Europe ' to the consideration and accumulation of facts from 

 all parts of this country and the Continent relating to Glacial 

 and Interglacial periods, gives the following as the result of 

 his investigations: — 



u We note/' he says, "as we advance from Pliocene times, 

 how the climatic conditions of the colder epochs of the Glacial 

 Period increase in severity until they culminate with the appear- 

 ance of that great northern rner cle glace which overwhelmed 

 all Northern Europe, and reached as far south as the 50th 

 parallel of latitude in Saxony. Thereafter the glacial epochs 

 decline in importance until in the Postglacial Period they cease 

 to return. The genial climate of Interglacial ages probably 

 also attained a maximum towards the middle of the Pleistocene 

 Period, and afterwards became less genial at successive stages, 

 the temperate and equable conditions of early Postglacial times 

 being probably the latest manifestation of the Interglacial 

 phase.'' (' Prehistoric Europe/ p. 561.) 



I shall now quote the same author's description of an Inter- 

 glacial Period as demonstrated by its flora and fauna. The 

 reader must, however, observe that by Pleistocene Period 

 Professor Geikie means the so-called Glacial Period with its 

 alternations of severe arctic climate and mild and genial con- 

 ditions. See p. 544, ' Prehistoric Europe/ 



"An examination/' he says, "of Pleistocene organic remains 

 leads us to conclude that strongly contrasted climatic condi- 

 tions alternated during the Period. At one time an extremely 

 equable and genial climate prevailed, allowing animals, which 

 are now relegated to widely-separated zones, to live throughout 

 the year in one and the same latitude. Hippopotamuses, 

 elephants, and rhinoceroses, Irish deer, horses, oxen, and 

 bisons then ranged from the borders of the Mediterranean as 

 far north at least as Middle England and Northern Germany. 

 In like manner, plants which no longer occur together — some 

 being banished to hilly regions, while others are restricted to 

 low grounds, and yet others have retreated to the extreme 

 south of the Continent or to warmer regions beyond the limits 

 of Europe — lived side by side. The tig-tree, the judas- tree, 

 and the Canary laurel flourished in Northern France along 

 with the sycamore, the hazel, and the willow. And we en- 

 counter in the Pleistocene deposits of various countries in 



