EXTINCT AND EXISTING GLACIERS OF COLORADO 49 



Much of the water of our mountain streams is from remnants of 

 glaciers and neve, and from snow-banks which form and are protected 

 in old glacial cirques. In a semi-arid region which is so dependent 

 upon irrigation, it is quite important to know whether the banks 

 of "perpetual snow" may be depended upon for the distant future, 

 as it may make a difference in the planning of extensive works. In 

 times geologically recent, the whole Southwest has become less humid 

 than formerly, and there are strong reasons for believing that the 

 desiccation is still in progress. Inherent difficulties in the use of 

 weather records for the determination of this question, even if they 

 covered a long enough period, make necessary more reliable methods, 

 which would be furnished by series of observations upon glacial 

 remnants and neve, carried through many years with records accu- 

 rately preserved by measurements and photographs taken from the 

 same points, with the same camera and lens, on the same day of each 

 year, preferably the last of August or first of September, for purposes 

 of comparison. 



Historical 

 It was long after the exploration and settlement of Colorado began 

 that the general glaciation of the higher mountains came to be 

 recognized. As late as 1872, Dr. Foster^ said that the mountains 

 nowhere exhibit roches moutonnees or other glacial phenomena and 

 that lakes are very rare. His travels must have been limited indeed, 

 for almost everywhere above 11,000 feet roches moutonnees, and mo- 

 raines are abundant and glacial lakes almost as common. Dr. Bliss,^ 

 replying to Foster, could give but very few examples of the hundreds 

 now known. Nine years later Geikie^ in his brief summary of Rocky 

 Mountain glaciation does not mention the existence of such phenomena 

 in Colorado, though a number of papers discussing the subject had 

 appeared long before. Endlich, Stevenson, Hayden, Marvine, King, 

 Peale, and perhaps others, between 1873 and 1878, published reports 

 in the publications of the several western surveys, describing glacial 



' Foster, J. W., "The Mountains of Colorado," Amer. Naturalist, Vol. VI, pp. 73-75. 

 ^ Buss, Richard, Jr., "Glaciers in the Rocky Mountains," Amer. Naturalist, Vol. VI, pp. 310-12, 1872. 

 3 Geikie, Archibald, "The Ancient Glaciers of the Rocky Mountains," Amer. Naturalist, Vol. XV, pp. 

 1-7, 1881. 



