No. 3.] MEMOIR ON GLACIERS. 181 



Notice of a iMemoir on Glaciers and Icebergs in re- 

 lation TO Climate, by Dr. A. J. Von Wceickofp. (In 

 the Proceedings of the Geoloo-ical Society of Berlin, 1881.) 

 With reminks by Principal Dawson, F.R.S. 



This memoir presents a very clear statement of the physical 

 causes and conditions of the accumulation and distribution of 

 snow and ice in different parts of the world, in illustration of the 

 possibility of the existence of continental glaciation in the Pleis- 

 tocene a<ie. The followini:; is a free translation of the author's 

 summary of his conclusions, which though suflBciently trite as 

 matters of physical geography, are deser»'ing of repetition at a 

 time when the principles of that science are treated with so 

 great contempt by certain schools of glacialists, 



1. The presence of water tends to moderate the extremes of 

 temperature both in pJ ace and in time. 



2. It does this, both by virtue of its great capacity for heat, 

 and by its cooling and heating powers when passing from the 

 solid into the liquid and gaseous states, and the reverse. 



3. These effVcts extend widely in place and time. For ex- 

 ample, near the south pole, the higher strata of air are warmed 

 by the abundant congelation of vapour into snow, and the snow 

 having fallen and havino- been chansied into the ice of ulaciers 

 and icebergs, is in that condition carried far to the north, and 



•hundreds of years after it has fallen as snow, is active in cooling 

 the ocean and the air as far north as the latitude of 40°. 



4. The general effect of the changes of condition of water, along 

 with the resulting formation of clouds and mists, is to raise the 

 temperature of winter and to depress that of sunjmer. 



5. The currents of the ocean have an especially great influence 

 in the mitigation of the extremes of teniperature, the direct 

 effect of whicli is much greater than that of the winds. 



6. The winds appear to act mainly in diffusing the tempera- 

 ture of the ocean currents. 



7. Though the winds may be in the first instance the motive 

 power of the main oceanic currents, yet the effects of the distri- 

 bution of land and of the form of the sea-bottom become para- 

 mount in influencing these when once set in motion. 



