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METEOROLOGICAL OBSERVATIONS. 
BAROMETER. 
November 22, 1768. A remarkable fall of the barometer all 
over the kingdom. At Selborne we had no wind, and not much 
rain ; only vast, swagging, rock-like clouds, appeared at a distance. 
PARTIAL FROST. 
The country people, who are abroad in winter mornings long 
before sun-rise, talk much of hard frost in some spots, and none 
in others. The reason of these partial frosts is obvious, for there 
are at such times partial fogs about ; where the fog obtains, httle 
or no frost appears : but where the air is clear, there it freezes 
hard. So the frost takes place either on hill or in dale, where- 
ever the air happens to be clearest and freest from vapour. 
THAW. 
Thaws are sometimes surprisingly quick, considering the small 
quantity of rain. Does not the warmth at such times come from 
below ? The cold in still, severe seasons seems to come down 
from above : for the coming over of a cloud in severe nights 
raises the thermometer abroad at once full ten degrees.* The 
first notices of thaws often seem to appear in vaults, cellars, &c. 
If a frost happens, even when the ground is considerably dry, 
as soon as a thaw takes place, the paths and fields are all in a 
batter. Country people say that the frost draws moisture. But 
the true philosophy is, that the steam and vapours continually 
ascending from the earth, are bound in by the frost, and not suf- 
fered to escape till released by the thaw. No wonder then that 
the surface is all in a float; since the quantity of moisture 
by evaporation that arises daily from every acre of ground is 
astonishing. 
* In such cases, the heat radiating from the surface of the earth is of course confined by the 
covering of cloud, and prevented from dissipating. — Ed. 
