426 



SUPPLEMENT. 



the moveable bottom is broad, and as high as the water 

 stands in the tube. And thus, the paradox is solved. 



The moveable bottom has no friction against the 

 inside of the box, nor can any water get between it and 

 the box. The method of making it so, is as follows : 



A B C D represents a section of the box, and abed 

 is the lid or top thereof, which goes on 

 tight, like the lid of a common paper 

 snuff box. .E is the moveable bottom, 

 with a groove around its edge, and it is 

 put into a bladdery^, which is tied close 

 around it in the groove by a strong waxed 

 thread ; the bladder coming up like a 

 purse within the box, and put over the 

 top of d at a, and all round, and then 

 the lid pressed on. So that, if water be 

 poured in through the whole / / of the 

 lid, it will lie upon the bottom JE, and 

 be contained in the space fEgh within 

 the bladder; and the bottom may be 

 raised by pulling the wire ', which is 

 fixed to it at JB : and by thus pulling the 

 wire, the water will be lifted up in the 

 tube k, and as the bottom does not touch 

 against the inside of the box, it moves without friction. 



Now, suppose the diameter of this round bottom to 

 be three inches (in which case, the area thereof will be 

 9 circular inches) and the diameter of the bore of the 

 tube to be a quarter of an inch ; the whole area of the 

 bottom will be 144 times as great as the area of the top 

 of a pin that would fill the tube like a cork. 



And hence it is plain, that if the moveable bottom be 

 raised only the 144th part of an inch, the water will 

 thereby be raised a whole inch in the tube ; and conse- 

 quently, that if the bottom be raised one inch, it would 



