2 THE POPULAR SCIENCE MONTHLY. 



dred feet below the present snow-line. Mount Rainier still carries a 

 dozen glaciers of considerable size, and all the country is glaciated 

 about this and the other 6now-peaks of Washington Territory, Mount 

 St. Helen's, Mount Baker, Mount Adams, Mount Olympus, etc., around 

 Puget's Sound, and on Vancouver's Island. In British Columbia, as 

 shown by George M. Dawson, Dr. Hector, James Richardson, and 

 others, the signs of ancient glaciation are conspicuous in all the high 

 country explored. Along the coast farther north the ancient glaciers 

 have left their marks in all the fiords, and those of the present day de- 

 scend lower and lower until in Alaska they reach the sea-level. 



The valleys of the Wahsatch range were once filled with masses of 

 ice as far south as Central Utah. A type of these, though not the 

 largest, was Little Cottonwood glacier, of which the record has been 

 carefully studied by the writer. It formed in a cirque at Alta ten to 

 eleven thousand feet above the sea, where its bed is everywhere con- 

 spicuously glaciated. It had a length of about ten miles ; its thickness, 

 as shown by the line of granitic blocks, left along its sides, was five 

 hundred feet or more, and its lower end protruded into the Salt Lake 

 Valley at a level not greater than fifty-five hundred feet above the 

 ocean. The glaciation of the Uintah Mountains has been graphically 

 described by King, who says that all the higher portions of the range 

 were once covered with a continuous sheet of snow and ice, and that 

 glaciers descended through all the important valleys ; also that the 

 ancient glaciers of the Uintahs occupied a greater area than all those 

 now existing in the Alps. 



In the Rocky Mountain belt the signs of ancient glaciers abound 

 from the northern part of New Mexico through Colorado and along 

 the great divide in Wyoming, Montana, and Idaho. In the valley of 

 the Arkansas, particularly about Leadville, in the Parks, on Clear 

 Creek, in the valley of the Rio Grande, roches montonnees, lateral and 

 terminal moraines, embankment-lakes, etc., all the work of glaciers, 

 have been observed by thousands of travelers. Here the mountain- 

 belt is very broad and high, is now the great condenser from which 

 radiate all the most important streams of the West, and in winter is 

 covered with a heavy sheet of snow. In ancient times it played a 

 similar r6le, only that the snows of winter did not melt as now in sum- 

 mer, but accumulated from year to year until they produced great 

 glaciers. In Wyoming the mountains are narrower and lower, and 

 the glacial signs are less conspicuous ; but toward the British line, 

 where the ranges multiply and the summits are higher, the records of 

 glaciation arc i vcrywhere apparent. 



To summarize the description of the glacial phenomena of this 

 Western region, it may be said that, over all the mountain-ranges north 

 of the limit heforc given, the traces of ancient glaciation are alike in 

 character and apparently of the same date, and are evidently the effects 

 of general and not local causes. 



