2 1 2 PREHISTORIC E UROPE. 



Even the hills of La Madelaine, which drain into the Loire, are 

 thought to have supported perennial snow and ice. 1 



But none of the old glaciers of Central France could vie with 

 the great ice-flows of the Pyrenees, several of which attained 

 colossal proportions, and deployed upon the low grounds at the 

 base of the mountains. According to MM. Martins and Collomb, 

 the ancient glacier of the valley of Argeles flowed from a height 

 of about 3000 metres for a distance of 53 kilometres, and depo- 

 sited its moraines upon the low grounds within 15 kilometres of 

 Tarbes, at an altitude of only 400 metres. The ice was not less 

 than 850 metres thick in a part of its course. The ancient 

 glaciers of the valleys of La Pique and the Garonne, as described 

 by M. Piette, were equally extensive, and their history, like that 

 of the Argeles glacier, is read in striated surfaces, roches mouton- 

 ntfes, perched blocks, lateral and frontal moraines, and wide- 

 spread sheets of till or boulder-clay — the moraine profonde of 

 the glaciers. On the Spanish side of the Pyrenees the glaciers 

 did not apparently attain so great a development. I may add 

 that the Cantabrian mountains, which are a continuation of the 

 Pyrenees, exhibit in the valleys that open to the north many 

 traces of considerable glaciers. 2 



The mountains of Central and Southern Spain also con- 

 tain relics of the Ice Age, glacial deposits having been noticed 

 in the Sierra Guadarrama to the north of Madrid, 3 and by 

 MM. Schimper and Collomb in the Sierra Nevada, where large 



Les Periodes Geologiques de VAuvergne, 1867 ; Delanoiie : Bull. Soc. Giol. France, 

 t. xxv. p. 402 ; Julien : Phenomenes Glaciaires dans le Plateau Central, 1869 ; 

 Marcou : Bull. Soc. Geol. France, 1870, p. 361 ; Das Ausland, 1872, pp. 460, 

 512 ; Fabre : Comptes Rendus de VAcad. des Sci., t. lxxvii. p. 495 ; Hooker : 

 Nature, yo\. xiii. p. 31 ; Symonds : Ibid., vol. xiv. p. 179. 



1 Tardy : Bull. Soc. Geol. France, 2 e Ser. t. i. p. 514. 



2 For descriptions and notices of glacial phenomena of the Pyrenees see — Char- 

 pentier : Essai sur les Glaciers, 1841 ; Bibliotheque Universelle de Geneve, t. lv. 

 (1845), p. 126; De Collegno : Ann. des Sci. Nat., t. ii. p. 191 ; Garrigou : Bull. 

 Soc. Geol. France, 2 e Ser. t. xxiv. p. 577 ; Martins and Collomb : Ibid., 2 e Ser. t. 

 xxv. p. 141 ; Brit. Ass. Rep. 1866, p. 52 ; Piette : Bull. Soc. Geol. France, 3 e Ser. 

 t. ii. p. 498 ; Comptes Rendus de VAcad. des Sci., t. lxxxiii. p. 1187. 



3 Don Casiano de Prado : Descripcion fisica i geologica de la Provincia de 

 Madrid, p. 164. 



