130 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



abroad. The reports themselves are models of perfection in 

 regard to typography and general execution, and are not to 

 be surpassed by the finest European works, whether published 

 by governments or private parties. It may be stated as a 

 well-known fact that much interest has been excited through- 

 out the scientific circles of Europe by the character of the 

 work done under the auspices of the state, and the utmost 

 admiration expressed in regard to its liberality and enter- 

 prise, this example being commended to European govern- 

 ments as eminently worthy of their imitation. 



SOUTH AMERICAN" GLACIERS. 



Professor Agassiz, in a letter dated July 29, and addressed 

 to Professor Peirce, makes a second communication in refer- 

 ence to the geological structure of Southern South America, 

 with special reference to the glacial phenomena heretofore in- 

 dicated by him. He refers to the broad Chilian valley, which 

 lies between the Andes and the coast range, and extends from 

 the Gulf of Ancud to Santiago, and still farther north. This 

 is a continuation, upon a high level, of the channels which, 

 from the Straits of Magellan to Chiloe, separate the islands 

 from the main-land, with the sole interruption of Tres Montes. 

 This great valley, covering some 25 of latitude, he considers 

 as a continuous glacier bottom, giving indications through- 

 out its entire length of the great southern ice-sheet which has 

 been moving northward in it. He found nothing to show that 

 glaciers had descended from the Andes and crossed this val- 

 ley so as to reach the shores of the Pacific. 



Between Currillo and Santiago, however, passing the gorge 

 of Tenon, he saw two distinct lateral moraines parallel to one 

 another. These were chiefly composed of volcanic boulders 

 resting upon the old drift, and indicated by their position the 

 course of a large glacier that once poured down from the 

 Andes of Tenon and crossed the main valley, without, how- 

 ever, extending beyond the eastern slope of the coast range. 

 These moraines are so well marked that they are known 

 throughout the country as the Cerillos of Tenon. 



He finds it difficult, in his brief communication, to describe 

 the successive retrograde steps of the great southern ice-field 

 that, step by step, left to the north of it larger or smaller 

 tracts of the valley free of ice, so that large glacial lakes could 



