GLACIER OF MT. ARAPAHOE, COLORADO 65 I 



the cloud mass even with the crests of the ridges, and passed 

 completely over the cirque instead of descending into it in any 

 notable measure, and sweeping the mist away. For nearly 

 half an hour after the clouds had been swept away from the 

 windward slope of the mountains, the cirque was more or less 

 obscured by shifting and eddying mists. These were at first 

 parts of the original cloud. Later they were mists formed 

 within the cirque. The latter formed the better index to the 

 action of the winds. From their behavior it was evident that 

 only secondary air currents came in actual contact with the snow 

 and ice of the cirque. 



Within the cirque the snow and ice are nearly all collected 

 into two masses. These seem to be essentially independent of 

 each other, and are separated by a ridge of debris. To the east 

 of this ridge is the smaller of the two. To the west of the ridge 

 is the larger — the main mass of snow and ice of the cirque. 

 The larger field was estimated to be nearly two miles wide. Its 

 length seemed to be approximately the same but I was not in a 

 position to make a satisfactory estimate of the length. Its sur- 

 face is steeply inclined. In several places where the snow and 

 ice extends to the top of the south wall, we measured the incli- 

 nation of its surface from above as carefully as possible by hold- 

 ing one climbing staff vertically and sighting down the slope 

 with another. The angle thus given showed an inclination of 

 about fifty degrees. At these points the upper edge which had 

 been melted back at its contact with the cliffs, showed a thick- 

 ness of twenty to forty feet. Over the bottom of the cirque the 

 slope of the surface of the ice is gentle enough for small bowl- 

 ders from the cliffs above to lodge on it. This gentler slope was 

 somewhat thickly covered in places with stones and small bowl- 

 ders. No large bowlders were seen on the surface, but below the 

 lower edge of the ice, are great numbers of rock-masses, ten to 

 twenty feet in diameter or even larger. It is probable that the 

 large bowlders gain momentum enough on the steep slopes above 

 to carry them over the gentler slopes and beyond the edge of 

 the ice" 



