Chap. 3-] Conduit Pipes . 



the orifices of the pipes, it will be .fc 

 one minute, 



1. The height of the refervoir being one foot, the 

 pipe of one inch and one-third diameter, in this cafe 

 there will be difcharged fix thoufand two hundred and 

 ninety-two cubic inches of water. 



2. The height of the refervoir being two feet, the 

 fame pipe will furnifh eight thoufand eight hundred 

 and ninety-three cubic inches of water. 



3. The height of the refervoir being one foot, and 

 the pipe two inches in diameter, there jvill be 'dif- 

 charged fourteen thoufand one hundred and fifcy-fix 

 cubic inches of water. 



4. The height of the refervoir being two feet, the 

 fame pipe will furnifh twenty thoufand and eight cubic 

 inches of water. 



It is eafy to perceive, that thefe quantities of water 

 are much greater than the correfponding quantities in 

 the above table ; and that the quantity furnilhed by 

 each pipe diminifhes, in faft, in proportion to its 

 length, becaufe there is then a greater fur face of fric- 

 tion. But it muft be remarked, that the diminution 

 of the quantity of water difcharged is not exaclly in 

 proportion to the length, of the pipe. The difcharge 

 is indeed dirainifhed as the pipe is made longer ; but 

 this diminution decreafes (if I may ufe the expreflion) 

 in the progrefs of the current ; for the firft thirty feet 

 the difcharge is diminilhed much more than in the fe- 

 cond thirty feet j and the third augmentation of thirty- 

 feet to the length diminifhes the difcharge fdlllefs than 

 the fecond; and fo of the reft. The refult of all this 

 is, that in common practice, where great precifion is noc 

 required, it may be laid down as a rule, that the quan- 

 tities of water difcharged in equal times, through the 

 fame horizontal pipe, under the fame height of the re- 

 fervoir, 



