Vol. 57.] CLIMATE OF THE PLEISTOCENE EPOCH. 477 



although under the influence of the I^Torth Atlantic depression, were 

 both glaciated ; and a general lowering of the mean temperature 

 might have led to an extension of glaciation from these centres 

 simultaneously. There were other factors besides distribution of 

 temperature to be considered, in tracing out the atmospheric circu- 

 lation, and meteorology was scarcely at present sufficiently advanced 

 to enable us to make certain deductions from its principles. 



Mr. A. E. Salter remarked that the theory advanced by the 

 Author required the existence during the ' period of maximum 

 glaciation in Europe ' of a similar anticyclonic area in Central 

 Asia. The diagrams and slides exhibited showed this very clearly. 

 In the paper, however, on ' Eecent Geological Changes in jSTorthern 

 & Central Asia' by Prof. G. E. "Wright (in the recently issued 

 number of the Quarterly Journal), it was stated, as a remarkable 

 fact, that in spite of careful research no signs of former extensive 

 glaciation could be detected in those regions. 



Mr. P. E. Kendall said that he thought the Author had wisely 

 made no attempt to explain the ultimate cause of the Glacial Period. 

 He agreed with Prof. SoUas that that belonged to some extra- 

 telluric agency, and was not the result of any modification in the 

 attitude of the earth in relation to the sun. Mr. Culverwell had, 

 he thought, shown very clearly that the eccentricity of the earth's 

 orbit in conjunction with processional movements was quite inade- 

 quate to produce a Glacial Period. Moreover the very recent date and 

 the long duration of the Ice Age were decisively against Croll's hypo- 

 thesis. At one time Interglacial periods were postulated upon very 

 insufficient grounds, but he had been convinced by recent discoveries 

 on both sides of the Atlantic that there had been mild intervals in the 

 Glacial Period. The Author's interesting and valuable speculations 

 offered a reasonable explanation of them, without invoking the 

 precession of the equinoxes. The speaker Could not share 

 Prof. Sollas's optimism regarding the possibility of correlating the 

 European and American Glacial and Interglacial deposits. 



Mr. J. LoMAs said that, although many workers in the past had 

 attacked the problems brought before the Society that evening, 

 none had been armed with the weapons which modern meteorological 

 research had placed in the Author's hand. If it were acknowledged 

 that glacial conditions ever existed over Xorth America and North- 

 western Europe, it followed that anticyclonic systems must have lain 

 over the same areas, and these must have been fringed by com- 

 plementary cyclonic systems. It seemed to him that the Author 

 had worked on perfectly sound lines in reconstructing the areas of 

 high and low pressure in the Pleistocene Epoch. It was quite obvious, 

 too, that if the two hemispheres were antic3'clonic at the same time, 

 a condition of affairs would be set up which would be unstable ; and 

 it appeared almost essential that the fact should be recognized on 

 meteorological grounds, that the Old and New Worlds were glaciated 

 alternately. If these two important principles could be established, 

 smaller points of detail might be left to adjust themselves. He did 



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