244 LOUIS AGASSIZ. 



this hyi'tothesis inadmissible. To a Yaloisiaii momitaineer, Perraiidin, 

 belongs the honor of solving the j)roblera. Observing that the glaciers, 

 at the present time, carry blocks, which they throw off at their extremity, 

 he explained the dissemination of the bowlders in question by the 

 hypothesis that the glaciers must have extended in times past much 

 beyond their present limits, and brought with them, on their surface, 

 material which they left when they retreated. He communicated this 

 idea to Chari)entier, who discussed it with him, and ended by adopting 

 it. The dispersion of the blocks is connected with other phenomena 

 which confirm this origin; the polished and rounded surfaces, the 

 accumulation of angular blocks, the hillocks, which have exactly the 

 form of moraines, the unstratified deposits, in which are foimd pebbles 

 covered with scratches — all these facts, which are repeated to-day in the 

 immediate vicinity of the glaciers which i^roduce them, also show that 

 these same glaciers once covered the larger part of Switzerland, leaving 

 the traces we have indicated. If Perraudin was the inventor of the 

 theory (1815), if Venetz contributed to its development (1833), it was 

 Charpentier who examined it, studied it, perfected it, made it known 

 (1835), and later disseminated it in the world of science with the authority 

 his standing gave him (1841). "To this ingenious and persevering 

 naturalist,'' said Alphonse Favre, ''should be given the greater part of 

 the glory attached to the discovery of this great scientific truth." 



Agassiz having heard of this discovery made a visit to Charpentier 

 for the purpose of combating it. He remained several months with 

 him and left well convinced of the truth of the theory, and full of eager- 

 ness to verify the proofs already advanced in its favor, to find new ones, 

 and, in short, to study the subject with the activity he carried into every- 

 thing. The question had been under discussion for some time when the 

 Helvetic Society of Katural Science met at ]S"euchatel, under his presi- 

 dency, on the 24th of July, 1837. The opening discourse turned upon 

 this question, and fell like a bomb in the midst of the most positive 

 adversaries of the glacial theory who happened to be present at the 

 meeting. 



Leopold von Buch, who was not famous for sweetness of temper, was 

 very angry, and would examine nothing, hear nothing in regard to the 

 matter. Agassiz, who had foreseen his opposition, had prepared the 

 following paragraph for the close of his speech to mollify him : " TTheu 

 Mr. de Buch affirmed for the first time, in the face of the formidable 

 school of Werner, that granite is of plutonic origin, and that the moun- 

 tains were raised, what said the ^eptunists? He was at first alone in 

 his support of the theory, and it was only by defending it with the con- 

 viction of genius that he made it i)revail. Happily, in scientific matters, 

 numerical majorities have never at first decided any question." 



Xotwithstanding the opposition of these great men, who had them- 

 selves contributed so much to the progress of science, the theory gained 

 ground, and is to-day generally admitted. 



