Chap. 2.] *fun bxrft by Jmall Quantity of Water. $13 



force upon the water below in the bellows 3 fliall fupporc 

 the weights, which are three hundred pounds ; nor will 

 they have weight enough to make them defcend, and 

 conquer the weight of the w~ater, by forcing it out of 

 the mouth of the pipe. 



It is clear from thefe principles, that the tun T O 

 (fig. 2.) rilled with water, may be-burft by prdfing 

 it with fome pounds additional weight of the fluid, 

 through the tube A B, which may be fuppofed to be 

 from twenty -five to thirty feet m height. From what 

 has been faid of the vefiel (fig. 6.) it indeed neceffarily 

 follows, that the fm all quantity of water which the 

 tube A B contains, prefles upon the bottom of the 

 tun as much as if a column of water had been added 

 as wide as the tun itfelf, and as long as the tube, which 

 would evidently be an enormous weight. 



II. The efFec~ls of gravity on fluids of different den- 

 udes will, from what has preceded, not be very diffi- 

 cult to comprehend. 



It has been obferved, that fluids are mafles of fmall 

 particles moveable with great facility among themfelves 

 independently of each other, preffing feparately and in 

 proportion to their maffes. 



It is proved alfo by chemical analyfis, that even 

 thefe minute particles are compofed of particles (till 

 fmaller. Now whether it refults from the interpo- 

 fition of caloric (or the matter of fire) in greater or 

 lefs quantities, which we know is the caufe of all 

 fluidity, and alfo of the difference that exifls between 

 the incomprefiible and elaftic fluids; or whether it 

 may depend upon the fhape or fize of the particles, 

 which, as in foliu bodies, may increafe or diminish the 

 porofity, it is certain, that there is a confiderable dif- 

 ference with rdpecl to denfity in'diffbrent fluids. 



From this, difference in point of dcniity, a reparation 



may 



