( IX ) 
3L Particle of Air,* and one of. .Water of equal Bulb 
then will the Weight pf, A be;.to thq)i Weight (Of.W/ 
as I to 85:0, their -Bulk?itbemg 4 cquabd if {the 
tide of Water be blown • up iqto 4 Bubble X'^) 'of'zo 
Times its Diameter,* then will-its Bulk be to uts 
Weight, as ,8oqq , to, .Sfp, whilfl: .a Sphere of Air 
(a) of. the lame Bignefs, has its Weight, as well as 
Bulk equal to 8000 Now if an ’Air Or: j^ura ^ rarer 
than common^ Air be luppofed within the watry Bub- 
ble to keep it-blown, it 'will be the fame as if ^ of 
the Air of (aj was carried into (w) and then the 
Weight of(^£>) would be encreafed by. the Num- 
ber 6000 ; fo that the Shell uof W^teri being in 
Bulk 8000, would be in Weight 85'od- 6000^ 685’o, 
whilft ap equal Bulk of Air weighed 8000,. and con-* 
fequcntly the watry Bubble ' would rife till it came 
to an Air, whofe Denlity is to the Denfity of the 
Air next to the Surface of the exhaling Water as 
6850 to 8000. , ) • , . ' 
This is the ftrongeft Way of Hating the Hypo- 
thefis. But to fupport it, the following Queries mull 
be anfwered. 
^ery ift. How comes the Aurdy or Air in the 
Bubbles, to be Ipecifically lighter than the Air with- 
out them, lince the Sun’s Rays, which ad upon the 
Water, are 'equally denfe all over its Surface? 
^ery 2d, If it could be poHible for a rarer Air to 
befeparated frorn the denier ambient Air, to blow up 
the Bubbles (as Bubbles of foaped Water are blown 
up by warm Air from the Lungs, whilll the am- 
bient Air is colder /and denier ) what would hinder 
that cold Air by its greater PrelTure, from reducing 
^ ' the 
