CHAPTER IX. 



ALPINE TRAVELS. 



FORBES spent the summer of 1840 at home, but in the 

 autumn of that year an event occurred which sent him 

 back to the Alps the following summer with renewed 

 interest. At the meeting of the British Association 

 held at Glasgow, he fell in with M. Agassiz, who, 

 already well known as a naturalist, had turned his atten- 

 tion to glacial phenomena, and had recently published 

 his * Etudes sur les Glaciers des Alpes.' Forbes was 

 already familiar with the general aspect of glaciers, and 

 had been much struck by what he saw of them. M. 

 Agassiz spoke of a series of observations which he pro- 

 posed to make on the Lauter-Aar Gletscher, of such a 

 nature as to entail a residence of some days in a hut on 

 the glacier itself, and invited Forbes to share his bivouac. 

 The invitation was gladly accepted, and Forbes accord- 

 ingly started for the Alps early in July 1841, accom- 

 panied by his friend and pupil John Mackintosh. 



After a short stay in Paris, they descended the Rhone 

 to Valence, and thence drove to Thuyetz, where Forbes 

 found himself once more among the ancient volcanoes of 

 the Vivarais. To these he devoted himself until his 

 rendezvous with Agassiz at the Grimsel, which was fixed 

 for the 8th of August. 



The six weeks which intervened were well spent. 

 'During my previous visit in 1839,' he writes, 'I had 

 found in the Vivarais a united attraction of scenery 



