254 James Geikie — On Changes of Climate. 



VI. — On Changes of Climate during the G-laoial Epoch. 



By James Geikie, F.E.S.E. 



District Surveyor of the Geological Survey of Scotland. 



Concluding Paper} 



[Continued from the May Number, p. 222.) 



IN a former paper '^ I referred very briefly to the succession of 

 glacial deposits in Switzerland. It was stated that no inter- 

 glacial beds like those of Scotland and America occur in the 

 Swiss grundmorane. But, as every geologist is aware, Professor 

 Heer and others have shown that the lignite-beds of the Cantons 

 of Zurich and St. Grail are really of interglacial age, since they not 

 only rest upon but are covered by glacial deposits.^ There can be 

 but one opinion as to the position in the series occupied by these 

 lignite- beds ; they are clearly intermediate in date between the 

 accumulation of the old grundmorane and the deposition of that 

 " moraine rubbish " which marked the new advance of the glaciers.* 

 This being the case, they cannot represent the beds that occur in the 

 " till " of Scotland, but must belong to a later stage. If this correlation 

 be correct, it seems to me that the Swiss beds will serve partly to 

 fill up a great blank in our record, and help us to realize the con- 

 dition of our country in the long ages that elapsed between the dis- 

 appearance of the great confluent glaciers and the subsequent period 

 of submergence, which gave rise to the "kames " and " esker-drift." 

 This will appear probable, as I hope to show, after we have taken a 

 glance at the glacial deposits in the north of Italy. 



Every glacialist knows that where the Dora Baltea issues from 

 the Val d'Aosta, to enter upon the plains of Piedmont, there occurs a 

 moraine of gigantic proportions. This moraine is not only remark- 

 able for its great size, but for the proof it afibrds that the mighty 

 glacier to which it owes its origin must have crept over the surface 

 of loose and incoherent deposits of sand and gravel without 

 materially denuding them. The section of the moraine and under- 

 lying deposits is given by MM. Martins and Gastaldi * as follows : 



3. Terrain morainique. 



2. Diluvium alpin. 



1. Sables Pliocenes marins. 



' For convenience of reference, the following is the order of appearance of the 

 earlier portions of Mr. James Geikie's paper " On Changes of Climate during the 

 Glacial Epoch." 



FirstPaper— Geol. Mag., Vol. Vni., Deer. 1871, p. 545. 



IX., Jany. 1872, p. 23. 

 „ Febry. „ p. 61. 

 „ March „ p. 105. 

 „ April „ p. 164. 

 „ May „ p. 215. 



Second 



Third „ „ 



Fourth „ „ 



Fifth „ 



Sixth „ „ 



2 Geol. Mag., Vol. IX., p. 61. 



3 The mammalian remains associated with the lignite-beds are Elephas antiqtius, 

 Rhinoceros Merkii, Jaeg., Bos primigenius, Cervus elaphus, and Ursus spelaus. See 

 Die Urwelt der Schweiz, p. 497. 



4 Geol. Mag., Vol. IX., p. 62. 



6 BuU. de la Soc. g^ol. de France, torn, vii., 2me. s^rie, p. 654. 



