286 THE LIFE OF JAMES D. FORBES. [CHAP. 



uniform, or bearing a ratio to their several distances from 

 the source of the glacier. The former experiment, I have 

 since learned, had been suggested by M. Studer to M. 

 Escher last year, who attempted to put it in practice 

 unsuccessfully, however on the Lauter-Aar Gletscher. 



* 3. The determination of the diurnal motion of a 

 glacier by reference to three co-ordinates/ 



After having arranged to meet Forbes at the convent 

 of the Great St. Bernard on the 12th of August, M. Studer 

 proceeded to make an excursion into the Tarentaise, 

 while Forbes vigorously prosecuted his survey, often 

 sleeping al fresco among the rocks of the Tacul, but 

 occasionally driven back to the friendly shelter of the 

 Montanvert by the weather, which was stormy and broken. 

 On the llth he crossed the Tete Noire to Martigny, 

 and next day the two friends exchanged hearty greetings 

 before the hospitable fire which, even in August, is the 

 chiefest luxury in the domicile of the worthy fathers of 

 the Great St. Bernard. 



To E. C. BATTEN, ESQ. 



'ORSIERES, NEAR GREAT Si. BERNARD, Aug. IStfl. 



' I am about to plunge into wild regions where 

 " Posts never come which come to all beside " 



' I talk of the summer as if it was to come ; and here 

 it is slipping through our fingers ! I have been already 

 two months in Switzerland, and now scarcely a month 

 of true summer remains. 



' I have left the Montanvert for the present, hoping 

 soon to return for the purpose of making a tour with 

 Professor Studer, of Berne, through the wild valleys 

 between the great St. Bernard and Monte Eosa : we 

 purpose making the tour of Monte Kosa together, and 

 I then return straight to Chamounix. 



' My experiments have been laborious, but successful. 

 I have such a quantity of unreduced observations, that 

 I am obliged to crave a general amnesty from my cor- 

 respondents for poor shabby letters ; and as I have a 

 prospect of sleeping in chalets for some time, pen and 



