AMONG THE GLACIERS. 29 



been in process of shrinkage. Such masses of debris could 

 never have been raised by the existing glaciers. Other attes- 

 tation of a former higher stage of the glaciers is seen in the 

 smoothed and striated rock-slopes which bound the glacier 

 valleys. These surfaces remind us of the smoothed and 

 striated rocks underneath the till in America. The records 

 of the glaciers may be traced on these smoothed slopes, two 

 or three hundred feet above the present ice-surfaces. 



At the foot of each glacier is a terminal moraine, which 

 is continuous with the two lateral moraines. Among the 

 Chamonix glaciers, this moraine is half a mile or more below 

 the termination of the ice, showing to what extent the glaciers 

 have diminished in length. These remote moraines were left 

 in 1817 and 1826. The " chief of guides" at Chamonix 

 remembers the occasion, and narrated to me a number of 

 memorable incidents. The plain between the moraine and the 

 foot of the glacier is strewn with bowlders. Many descend 

 on the surface of the ice or imbedded in its mass. One sees 

 them frequently precipitated from the foot of the Glacier des 

 Bois to the plain below. The diminution of the glaciers ap- 

 pears to be a persistent phenomenon, and not dependent on 

 climatic fluctuations of short period. There must be either a 

 continuous diminution of cold or of precipitation. 



All parts of the glacier mass move continually downward. 

 In the Glacier des Bossons the amount of the movement has 

 been determined by means of a catastrophe. In 1820, eight 

 persons were buried in the Grande Crevasse at the foot of the 

 dome of Mont Blanc. In 1861, their remains began to ap- 

 pear in the ice near the termination of the glacier. In forty 

 years they had traveled 26,000 to 29,000 feet, or 680 feet a 

 year. As they were buried 200 feet beneath the surface, it 

 appears that 200 feet had been melted from the top of the 

 glacier in the same interval. The Mer de Glace, as shown 

 by Forbes, moves past Montanvert at the rate of 822 feet 

 per annum. Near the foot of the Glacier des Bois the motion 

 is 209 feet a year. The lower Glacier of the Aar, which was 

 the scene of Agassiz's observations, moves downward at an 



