GENERAL MEETING. ng 
solar radiation. Attention will here be restricted to the last-men- 
tioned cause. 
An augmentation of the strength of solar radiation (a) will cause 
a general rise in the temperature of the atmosphere, (0) will heighten 
the contrast between warm and cold regions, thereby stimulating 
oceanic and atmospheric circulation, and (ce) will heighten the con- 
trast between wet and dry regions, making the wet wetter and the 
dry drier. (d) It will also diminish glaciation. This has been dis- 
puted by some writers, but is sustained by a quantitative discussion. 
A computation, based on the annual curves of precipitation and tem- 
perature at St. Bernard, close to the glaciers of the Alps, shows that 
a general rise in the temperature of the air, while it will increase the 
total precipitation, will slightly diminish the snow-fall ; that it will 
very greatly increase the rate of melting. The ratio of snow-fall 
to evaporation is reduced one-half by 6° C rise of temperature ; 
the ratio of snow-fall to melting is reduced one-half by a rise of 
13°; and, assuming that evaporation actually dissipates twice as 
much snow as does melting, the ratio of snow-fall to snow dissipa- 
tion (or the tendency to glaciation) is reduced one-half by 42° rise 
of temperature.* 
(e) Increase of solar radiation will also, through its general 
effects, influence the distribution of winds, and thus produce sec- 
ondary effects of a local nature. 
Mr. Dawu remarked that ice was rendered more plastic and 
fluent by the presence of water; so that the movement of ice and 
the consequent. extent of glaciers are favored by rain. If Mr. 
Gilbert by the term “ glaciation” referred to the extent of glaciers, 
some limitation of his conclusions might be necessary. 
Other remarks were made by Messrs. ANTISELL, DooxiTrLe, H. 
FarquuHar, and Exv.iort. 
The next communication was by Mr. J. W. CHIcKERING on 
THE THERMAL BELTS OF NORTH CAROLINA. 
[ Abstract. ] 
In the agricultural volume of the Patent Office Report for 1861 
is an article written by Mr. Silas McDowell, of Franklin, Macon 
county, N. C., bearing this title. He was a man of much intelli- 
* The computation is given in full in “ Science’’ for March 16, 1883. 
