Water blowing machine. ^a 



Without any lateral openings to the air: laftly he obferveSi 

 that air conveyed downward from the top of the tube, or the 

 funnel, prevents the introduction of the frefh air by the lateral 

 apertures, which in this cafe, inftead of receiving more air, 

 let that which has been already introduced efcape. 



Lewis concludes, that the two methods by which air may 

 be made to defcend with a ltream of water, ought not to 

 be united in one machine ; and that the machine confirucled 

 with a pipe, a funnel, and apertures to let the air enter 

 around or below the throat, produces the molt powerful 

 efTea. 



The machine on which we made our experiments was of The machine of 

 the conftruaion which Dr. Lewis has deemed moll advantage- J-™^** de ~ 

 ous. See Fig 2. 



The height of the fall, taken from the bottom of the channel Height of the 

 that conveys the water to the upper part of the barrel B, is u ' 

 21 feet 6 inches. 



The height of the funnel, from the bottom of the fame Funne! at top 

 channel to the throat x, is feven feet. This funnel is of the ofthi PPe- 

 fhape of a frufrum of an inverted cone, the larger diameter / 



of which is J 2 inches, the fmaller four. The remainder of 

 the tube down to the barrel, is a cylinder eight inches in 

 diameter. 



The plank N, 12 or 13 inches wide, is fixed one foot Barrel or ait 

 below the head of the barrel. The barrel is fix feet high. V( frd * 



The water iffues out of the barrel by the triangular apertures The wit r flow* 

 1 1 1, and is conveyed away to a drain by the channel M, the oft beneath > 

 bottom of which is four feet higher than that of the barrel* 



The air comprefTed by the external water, the level of an d the air \% 

 which, as will foon be proved, is from 27 to 30 inches above c °nveyed 

 that of the water in the barrel, efcapes through the tube P, it top. 

 Which is a hollow cylinder five inches in diameter. 



This tube P, called alfo the air-pipe, terminates in a conical Air-holes in tb* 

 nozzle, having an aperture of two inches only. upright pipe. 



Immediately below the throat x, are four air-holes y y. 



This being premifed, we proceed to the inftrument em- 

 ployed by us for determining the denfity of the air in the 

 machines. 



It was invented by Citizen Vergnies Bouifchere, pro- Ga g ef ?* 

 prietor of the iron works at Vic-Deifos, in the ci-devant ^nfity'of th* 



Vol. XII.*-Sjb.FTEMBJiR, 1805. £ county air. 



