SS^ CALCULATIONS for 



E. The boiler, which may he either iron or copper. 



F. The hot-well for iupplying the boiler with water. 



GG. Two cifterns under the level of the water, in which the 



fmall bores BB, and the condenfer are contained. 

 HHH. The furface of the water with which the fleam-engine 



and water-wheel are fupplied. 

 aa. The fteam-pipe, through which the fteam is conveyed from 



the boiler to the receiver. 

 I?. The feeding-pipe for fupplying the boiler with hot water. 

 ccccc. The condenfing apparatus. 

 dd. The pipe which conveys the hot water from the condenfer 



to the hot-well. 

 eee. Valves for admitting and excluding the water. 

 ff. The injeftion pipe, and g the injeftion cock. 

 /}. The condenfer. 



It does not appear neceflary to fay any thing here on the 

 manner in which this machine performs its operations without 

 manual affiflance, as the method of opening the cocks by which 

 the fteam is admitted into the receiver and condenfed, has been 

 already well defcribedby feveral writers. But it will be neceffary 

 to remark that the receiver, penftock, and all the pipes, mufl 

 be previoufly filled before any water can be delivered on the 

 wheel, and when the fteam in the boiler has acquired a fuffi- 

 cient ftrength, the valve at c is opened and the fteam immediate- 

 ly ruflies from the boiler at E into the receiver A, the water 

 defcends through the tubes A and B, and afcends through the 

 valve e and the other pipe or tube B into the penftock C. This 

 part of the operation being performed and the valve c fliut, that 

 at a is fuddenly opened, through which the fteam ruflies down 

 the condenfing pipe c, and in its paflage meets with a jet of cold 

 water from the injeftion cock g by which it is condenfed. A 

 vacuum being made by this means in the receiver, the water is 

 driven up to fill it a fecond time through the valves ee by the 

 preffure of the external air, when the fteara-valve at c is again 

 opened and the operation repeated 'for any length of time the 

 machine is required to work. 



There are many advantages which a fteam-engine on this 

 conftruftion poflefles beyond any thing of the kind hitherto in- 

 vented J a few of which I fliall beg leave to enumerate. 



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