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prcflcs and confines this air in the Apples, 

 muft be equal to the weight of 48 of out 

 atmofpheres, when the Mercury in the ba- 

 rometer Hands at fair, that is 30 inches high. 

 Now a cubick inch of Mercury weigh- 

 ing 3 5 80 grains, thirty cubick inches (which 

 is equal to the weight of our atmofphcrcon 

 an area of a cubick inch) will weigh 1 5 

 pounds, 5 ounces, 215 grains; and 48 of 

 them will weigh above 736 pounds j which 

 is therefore equal to the force with which an 

 inch fquarc of the furface of the Apple 

 would comprefs the air, fuppofing there 

 were no other fubftance but air in the Ap- 

 ple : And if we take the furface of an Ap- 

 ple at 16 fquare inches, then the whole 

 force with which that furface would com- 

 prefs the included air, would be 1 1 776 pounds. 

 And fince aclion and rea&ion arc equal, this 

 would be the force, with which the air in 

 the Apple would endeavour to expand it felf, 

 if it were there in an elaftick and ftrongly 

 coraprcflcd (late : But fo great an expanfive 

 force in an Apple would certainly rend the 

 fubftance of it with a ftrong exploflon, es- 

 pecially when that force was incrcafed, by 

 the vigorous inEuence of the Sun's warmth. 



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