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fome liquid, fuch as water or blood, or any other fluid ; and in the 

 larger tube let there be a pillon or forcer, as a A B. Now, I fay, 

 that if the liquid in this tube be comprefl'ed, the fmall branch, B, 

 which is next the forcer, will not endure a greater preflure than the 

 branch, F, which is the moll ditlant from it. 



And though the fmalletl tube, F, be a million times lefs than the 

 largell one, the preflure of the liquor will be the fame in both. 

 To illurtrate this by another example. Let the diameter of this 

 largell round tube be reprefented by a fquare veflel, fg. 5 , A B C 

 DE F, the meafure of one of whofe fides lliall be as 5, the fquare 

 of which is 25 ; then let the fmall round tube be reprefented by 

 a fquare one, as ?itfig. 0, which call 1, being formed of one of the 

 divilions oi fig. 5, then this fmall fquare tube will be to the large 

 fquare veflel in the proportion of 1 to 25. 



Now, let us fuppofe the large fquare veflel to be filled with fome 

 liquor, which is prefled with a force equal to one hundred pounds, 

 the bottom of the veflel, AFE, befides the weight of the liquor, 

 will futfer a preflure of one hundred pounds; but to prefs the bafe 

 of the veflel. Jig. Q, H, with the like force, will only require a 

 wreight of four pounds ; and if lb, the preflure on the bafe H will 

 be exactly proportioned to the prefl^ure on the bafe AFE, becaufe 

 this is twenty-five times larger than H. And we may even fay, 

 that if only the weight of a grain of fand was imprefled on the 

 part a AB, infg. 4, there is no reafon why this preflure fliould not 

 be felt in all the fmaller tubes at the fame moment as in the larger 

 one ; for, as the whole of the water or other fluid is to be confi- 

 dered as a folid body, there is nothing to prevent fuch impreflioh 

 being fo felt. 



Thefe reafonings of mine will be very eafily underftood by any 

 one who is acquainted with the principles of hydrollatics, as laid 

 down by Stevinus. 



But if we fuppofe the part A, in. fig. 4, to be fome feet higher 

 than F or L, it may be faid that the water in the fmall tubes, F and. 



