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air of gufts, and hurricanes cold, tliough in hot 
climes and feafons ; it coming from above. 
The cold air defcending from above, as it pene- 
trates our warm region full of watry particles, con- 
.denfes them, renders them vifible, forms a cloud 
thick and dark, overcafling fometimes at once, large 
and extenlive j Ibmetimes, when leen at a diftance, 
fmall at fiift, gradually increafingi the cold edge, 
or furface, of the cloud, condenfing the vapours next 
it, which form fmaller clouds, that join if, encreafe 
its bulk, it defcends with the wind and its acquired 
weight, draws nearer the earth, grows denier with 
continual additions of water, and difcharges heavy 
fhowers. 
Small black clouds thus appearing in a clear fky, 
in hot climates, portend florms, and warn feamen to 
hand their fails. 
The earth turning on its axis in about 24 hours, 
the equatorial parts mufl move about 15 miles in 
each minute. In northern and fouthern latitudes this 
motion is gradually lets to the poles, and there no- 
thing. 
If there was a general calm over the face of the 
globe, it muff be by the air’s moving in every part, 
as faff as the earth, or fea, it covers. 
He that fails, or rides, has infenfiblv the fame 
degree of motion, as the (hip, or coach, with which 
he is conneded. If the fhip flrikes the diore, or the 
coach ffops fuddenly, the motion continuing in the 
man, he is thrown forward. If a man were to 
jump from the land into a fwift failing fliip, he 
would be thrown backward (or towards the Hern) 
not having at firft the motion of the fliip. 
He 
