CONSTRUCTION OF AN HYDRAULIC APPARATUS. 3X 



When the veflel B is tilled, and A is emptied, the cock in the 

 air pipe begins to be put in motion, but before the tube 1 is 

 connected to the branch above 3, the fmall conical valve above 

 B clofes its air pipe ; the valve under B being now clofed by 

 the prefliire of the water in the tubes L S, the water in B is 

 forced down the pipe under 3, and carried away with the 

 itream : the condenfed air is let out of A, and this veflel re- 

 plenifhed with water. 



The air which is carried down the ftream while it can enter 

 into neither veflel above, will collect in V, until an avenue to 

 one is completed, through which it will rapidly afcend. If 

 the engineer does not like the conftructi'on of the cock I have 

 recommended, its place may be fupplied by two of the com- 

 mon kind, with adjufting pieces upon their keys. . , 



The condenfed air collected in the veflel V, may be applied 

 to the purpofe of raifing water either above the refervoir C C, 

 or below the veflel V, merely by forcing the air out of V into 

 the veflel containing the water, by the preflure of the water 

 in the pipes L S. 



The apparatus will begin its operations without any trouble ; 

 the capacities of the veflels A B are indeterminate ; and if the 

 higher orifice of the pipe S be contracted, the machine will 

 work with a lefs quantity of water than it may be calculated 

 to receive. The veflels A and B however, fhould always be 

 filled completely with water before the admiflion of the con- 

 denfed air, otherwife the quantity of raifed water will de- 

 creafe. 



A model was conftru&ed to illuftrate the principle: the Experimental 

 two water pipes were about half an inch in diameter, and only tri *k 

 one fmall hole was made at the higher end of the longer. Into 

 the top of the veflel reprefented by V, was foldered two fmall 

 pipes, which were furrounded by a little thread, and inferted 

 into the neck of a fmall glafu bottle. The veflel V and the 

 lower parts of the water pipes were plunge4 into a veflel of 

 water, until all the air in the apparatus below the liirface was 

 expelled. In this fituation the bottle, previoufly filled with 

 water, was fixed upon the pipes above V. The model being 

 lifted out of the water, and the longer pipe fixed to a fmall 

 ciftern, the remaining parts of the water pipes were carefully 

 filled ; a fuflicient fuppiy was let into the ciftern, and the 



higher 



