370 Reviews — C. Reid — Buhiixerged Forests. 



water at Alandgardlek and 678 at Tuaparsuit, down to 104 at 

 Jacobshavn. J. E. Man- (Geol. Mag., 1887) said that results in 

 Greenland sliowed a variation from 200 grammes in one river to 

 9,744 in another. 



Great glaciers still exist in British Columbia and Alaska, but are 

 receding rapidly. The Muir Glacier in Alaska when seen by 

 Vancouver in 1794 filled the inlet 25 miles farther down than it does 

 now. I may say that Vancouver's statements and surveys were 

 remarkablj^ correct. The supposition that the recession of the 

 glaciers in this area is comparatively recent is borne out by the fact 

 that the surface disintegration as shown by excavations is practically 

 nil. Also, we have some evidence of a rapid fall of the lake-level in 

 old Indian kekwullie houses, which were pits roofed with logs and 

 boughs and then covered with earth. At two points on Kamloops 

 Lake similar huts exist about 70 feet above high water. They are 

 always built as near to water as possible. One of these is at least 

 two hundred yards above the level of the water. But about fifty 

 years ago some were inhabited near the lake as low as 15 feet above 

 high-water mark. There seem to be none between these two stages, 

 suggesting a rapid fall in the water-level. 



liegarding my estimate of 10,100 years, I may also note that 

 Warren Upham allows 5,000 years for the erosion of glacial drift and 

 5,000 years for the Champluin period, which includes the period of 

 retreat of the glaciers. My figures for this would be as above, 9,800. 

 Professor Wright estimates 7,500 years for the streams tributaiy to 

 Lake Erie to cut their valleys, a work which commenced after the 

 retreat of the glaciers. Professor N. H. Winchell estimated 8,000 

 years for post-glacial erosion of the Mississippi gorge from Fort 

 Snelling to St. Anthony Falls; G. K. Gilbert 7,000 years for the 

 recession of Niagara Falls, which commenced soon after the close of 

 the Glacial period. Against this must, however, be set the opinion 

 of Dr. J. W. W. Spencer in his exhaustive report on the recession of 

 the falls for the Geological Survey of Canada, in which he estimates 

 39,000 years as the period required, which he considers might be 

 reduced 3,500 years by admitting Russell's theory of the Erie 

 discharge. If the suggestion advanced by Dr. Pohlmann to the effect 

 that the river re-excavated an old channel from the whirlpool to 

 Queenston were correct this might be further reduced. The writer 

 is not competent to judge as to this, but the retreat of the glacier 

 from the high ranges of the Western Cordillera would probably be 

 much later than in the east. It is generally admitted that the glacial 

 stage of North America endured later than that of Europe. 



E-EJ-VIE-V^S. 



I. — Submerged Forests. By Clement Reid, F.R.S. 8vo ; pp. viii, 

 129, with 1 plate and 4 text-illustrations. Cambridge: at the 

 University Press, 1913. Price Is. net. 



IN this clearly and concisely written little book we are taught the 

 lessons that can be learnt from a careful study of submerged 

 forests by a geologist who is the chief authority on the natural 



