190 FRAGMENTS OF SCIENCE. 



100 hours the maximum motion of the three lines respec- 

 tively is as follows: 



Maximum Motion in 100 hours. 



Line A 56 inches. 



* B 45 " 



C , 30 " 



This deportment explains an appearance which must 

 strike every observer who looks upon the Morteratsch from 

 the Piz Languard, or from the new Bernina road. A 

 medial moraine runs along the glacier, commencing as a 

 narrow streak, but toward the end the moraine extends 

 in width, until finally it quite covers the terminal portion 

 of the glacier. The cause of this is revealed by the fore- 

 going measurements, which prove that a stone on the 

 moraine where it is crossed by the line A approaches a sec- 

 ond stone on the moraine where it is crossed by the line C 

 with a velocity of twenty-six inches per one hundred hours. 

 The moraine is in a state of longitudinal compression. Its 

 materials are more and more squeezed together, and they 

 must consequently move laterally and render the moraine 

 at the terminal portion of the glacier wider than above. 



The motion of the Morteratsch glacier, then, diminishes 

 as we descend. The maximum motion of the third line is 

 thirty inches in one hundred hours, or seven inches a day 

 a very slow motion; and had we run a line nearer to the 

 end of the glacier, the motion would have been slower 

 still. At the end itself it is nearly insensible.* Now I 

 submit that this is not the place to seek for the scooping 

 power of a glacier. The opinion appears to be prevalent 

 that it is the snout of a glacier that must act the part of 

 plowshare; and it is certainly an erroneous opinion. The 

 scooping power will exert itself most where the weight and 

 the motion are greatest. A glacier's snout often rests 

 upon matter which has been scooped from the glacier's bed 

 higher up. I therefore do not think that the inspection of 

 what the end of a glacier does or does not accomplish can 

 decide this question. 



* The snout of the Aletsch Glacier has a diurnal -motion of less 

 than two inches, while a mile or so above the snout the velocity is 

 eighteen inches. The spreading out of the moraine is here very 

 striking. 



