1841-42-] JOHN TYNDALL. 205 



Agassiz and all his collaborators and friends certainly 

 worked hard and with a determination to penetrate all 

 the secrets of the glaciers, and some of their observa- 

 tions and experiments are excellent and valuable ; but it 

 is no injustice to any of them to say that they were not 

 sufficiently equipped and prepared for the work they 

 had rather rashly undertaken. Devotion to progress of 

 science was not sufficient ; something more was required. 

 De Charpentier and Bishop Rendu had already said all 

 that could be expected from men not trained as physi- 

 cists. Agassiz added very little, if any, to their work. 

 What was wanted was a great physicist, to solve the 

 problem of glaciers. James D. Forbes proved unequal 

 to the task ; and it was reserved for John Tyndall, the 

 great pupil and successor of Faraday, as the discoverer 

 of " radiant heat," to explain fully the origin of glaciers, 

 the pressure theory, regelation, crystallization and inter- 

 nal liquefaction, the veined structure ; in fact, all the 

 mechanism of glaciers. The principles set forth in 

 Tyndall's "The Glaciers of the Alps" (London, 1860), 

 come next to the great discoveries of Venetz and de 

 Charpentier, and to Agassiz's Ice-age. The four com- 

 plete the survey of the subject. 



In November, 1842, Agassiz, losing patience with the 

 constant attacks in German newspapers directed against 

 him by his formerly intimate friend, Dr. Karl Schimper, 

 published a pamphlet entitled " Erwiederung auf Dr. 

 Karl Schimper's Angriffe," four-page quarto, for pri- 

 vate circulation, though it was freely distributed, more 

 especially in Germany and Switzerland. It would have 

 been better Agassiz had ignored these attacks ; but 



