412 Obfervations on the Flux and Reflux 
from weft to eaft, and therefore produce a continual eaft 
wind in the parallel of the atmofpheric tide. A wind alfo 
will proceed from the north or fonth of this parallel, in an 
oblique direction north and fouth, to the diftance of about 
thirty degrees on each fide of the equator. In both the tem- 
perate zones the regular winds muft blow from weft to eaft 
within thefe boundaries, as they incline towards the parallel 
of the atmofpheric tide, and again reftore the equilibrium of 
the atmofphere, which has been rarefied by the continual 
movement of the aérial tides. Thefe confequences, deduced 
from theory, coincide perfeétly with the courfe of the wind 
in the ocean. At land, and on confined feas, many other 
caufes exift which contribute to change the regular direGtion 
of the winds, and to make them variable. 
On the coafts, in the torrid zone, the wind blows for the 
moft part from the fea towards the land. The reafon of this 
is evident. The reflected rays of the fun, and other caufes, 
heat and rarefy the air at land much more than at fea; and 
the direGtion of the wind always proceeds towards the rare- 
fied part of the atmofphere. The places where the laf men- 
tioned winds feparate *themfelves from the regular winds, 
“muft be abfolutely calm. All this is confirmed by experi- 
ence throughout the whole torrid 20 and particulatly oa 
the coa{t of Guinea. 
Befides the determination i courfe of the winds in 
confequence of the atmofpherit flux and reflux, there are 
an immenfe number of local and accidental caufes whieh 
have an influence on the creation and direction of the winds. 
One of the leaft irregular is the preffure < and gravity of the 
atmofphere in the fricid zones, which mutt occafion a con- 
tinued movement of ‘the air towards the more rarefied parts, 
and at the fame time a wind from ‘the poles towards the 
equator. As foon, however, as this continual wind enters 
the temperate zones, its direction will be overcome and de-. 
ranged by other local caufes: an examination, however, af 
thofe winds not arifing from the atmolpheric tides, does nat 
fall within the plan of this effay. 
Thofe winds, on the other hand, which ongule blow 
at fun-rife and fun-fet, are a shoitha ble effect of the atmo- 
fpheri¢ 
