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REPORT — 18G9. 



Aar. If not already done, the glacier and the surrounding mountains ought 

 to be well surveyed and mapped, and its moraines clearly expressed. 



Secondly. The amount of rocky and earthy matter forming each medial 

 and lateral moraine would require to be determined as accurately as possible, 

 probably in the manner illustrated by the accompanying rough diagram of 

 an imaginary glacier. 



Take of the medial moraine marked a a space, say, from 100 to 500 yards in 

 length, and estimate the solid contents of that portion of the moraine. This 

 should be done as near as possible to the place where the medial moraine is 

 formed by the union of the two lateral moraines x and 3/; for lower down part 



of the material may disappear by falling into crevasses. The same must be 

 done for the moraines h and c, or for each medial moraine ; and also, in several 



