VEGETABLES. 
363 
now in segments^ and sometimes in irregular patches and 
spots. Wherever they obtain_, puff balls abound ; the seeds 
of which were doubtless brought in the turf. 
METEOROLOGICAL OBSERVATIONS, 
BAROMETER. 
OVEMBER 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, rocklike clouds 
appeared at a distance. 
PARTIAL FROST. 
The country people, who are abroad in winter mornings 
long before sunrise, 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, little 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, wherever 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 suffered to escape till released by the 
