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experiment farther, I Ihould have attempted to have 
extracted all the air by a milder heat of about no 
degrees, in vials inverted in the water bath ; fo as 
that, while the air arofe into the vials, an equal por- 
tion in bulk of the water might have been received 
into bladders fitted to them ; or Ihould have made 
ufe of other methods, which I fhall have occafion 
hereafter to defcribe. 
Experiment IV. 
I took a glafs receiver, of a cylindric form, near 
54- inches high, and 34. inches in diameter, which 
contained 25 oz. 150 grains of water, Troy weight; 
or in meafure 45-4-44 cubic inches, according to the 
above calculation of 26;^ grains of water to the cubic 
inch. This receiver being immerfed in a ciftern of 
water, was there turned, with its mouth downwards, 
and then raifed, thro’ a hole in a board fitted to the 
top of the ciftern, as in Fig. 3. The receiver 
was there firmly fecured with wedges, in fuch man- 
ner as to continue full of water, the lower part of it 
remaining immerfed in the water of the ciftern. 
I then took a Frontinijic vial, which contained nine- 
teen ounces five drachms of water : this was filled 
with frelh pure air, by emptying it of the water in 
a cool open place, and then ftopping it with a cork. 
The vial, thus filled with air, was placed, in an erect 
pofition, under the receiver; and the cork being ta- 
ken out, the air afeended into the receiver, as it was 
forced out of the vial by the water rufliing into it. 
Into this air a moufe was conveyed, by placing it on 
a round piece of cork, and plunging it quickly thro’ 
