﻿4 68 



SMITHSONIAN MISCELLANEl IUS COLLECTIONS 



[vol. 47 



years and gives a clue to the amount of longitudinal compression to 

 which the ice must be subjected from year to year. 



There remains still another striking feature, especially well shown 

 upon the Lefroy, Wapta, Illecillewaet and Asulkan glaciers, to 

 which the name " dirt hand " is also applied and which may 

 best be briefly described here for comparison with the preced- 



Fii 



— "Dirt stripes," side of [llecillewaet glacier. The lamina- here would 

 ie conformable with the strata, providing the hitter were present. 



ing types, with which it has absolutely no connection. Much con- 

 fusion has arisen in the thinking, the oral discussion and the litera- 

 ture because these three entirely independent features have not been 

 dearly distinguished and separatel) named. The first two can be 

 recognized to the lust advantage at a considerable distance, this 

 last must be seen at close range, along the margin of a glacier fairly 

 free from coars< debris, and subjected to more or less siiri ice melt- 

 ing. The surface here looks as though it had been swept with a 

 wire broom, the strokes being very long and regular and parallel 

 with the side of die glacier. The hue dirt, mostly wind-blown, is 

 arranged in delicate, parallel streaks separated by similar streaks 



