256 On the Animal Calculus. 
rife ill the Form of Vapours, perpendicularly 
upwards, in a dill Air. But if that Air be 
in a progreffive State cowards any Point what- 
foever, the Vapours are then cdnftaritly car- 
ried along with it, in a more or lefs oblique 
Courfe, according to the different Celerity 
of the Stream of Air. Heat is Co far from 
attrafting watry Vapours towards itfelf, that 
it on the contrary repells them erery way from 
itfelf. 
2. What has probably led Men into this 
Miftake, is the common Obfervation, that 
when a wet Cloth is held before a Fire, the 
Vapours which arife from that Cloth, move 
conftantly towards the Chimney in which the 
Fire is: Which Tendency is not owing to the 
Attraftion of the Fire, but to the Force of the 
Scream of frefh Air, which is continually 
flowing in, to fupply the Place of the Air, 
which being ratified by the Heat of the Fire 
is inceffantly afeending up the Chimney. 
. 3. As it is obferved that we have here in 
land more Southerly and South Weft Winds, 
than from the oppofice Points, fo the Vapours 
muft on that Account be blown more to the 
Northern than to the Southern Sides of Rivers. 
But the different Degrees of Healthinefs of 
one 
