{gj{, SYPHON APPARATUS. 



lifts the little ball H at the end of the lever, and confeqaently 

 the weight E ; and in defcending it ads upon the bail I, and 

 forces the weight E in the contrary diredion, A fide viewr 

 of this apparatus is prefented in Fig, 4. where the double 

 openings in the cocks A, B, and the manner of fixing the 

 weight E with its levers, are more diftindlly feen. 



In Fig. 2. the air-veflel is fuppofed half filled with air 

 tranlinitted from the cooler. The cock B is fhut, and the 

 cock A open, admitting water in place of the air. The floater 

 is afcending, and when the fork O touches the ball H^ the 

 weight E is Hfted, the quadrant begins to move from E to G, 

 but the Aiding part mn remains in its place till the weight E, 

 having pafTed the perpendicular and falling over the other 

 .. fide, brings the point F in contaft with n, and forces at once 



both cocks in the contrary direflion ; by which A being (hut 

 and B open, the air from the cooler rifes, and the water 

 defcends. The floater confequently finks till it prefies upon 

 I, drawing the weight E in its firft fituation, and turning the 

 cocks again. This procefs will evidently continue to al- 

 ternate. 



Every mechanical reader will fee the neceflity of turning 

 the cocks in this apparatus by a fudden ftrpke. For if the 

 floater were to z6t diredly and conftantly upon them ; there 

 would be a certain moment when both would be (hut, and 

 confequently the motion would ceafe. 

 Another method Inftead of the Aider m n, the fame effe6l may be produced 

 by c ains. 1^^ ^^^ chains, {Fig. 5.) on the ends of the levers FG, con- 

 nected with the cock A ; the other apparatus remaining as 

 defcribed above. This method may even in fome refpeCts ap- 

 pear more Ample; but I have defcribed the other partly be- 

 caufe I apprehend the contrivance to be new, and partly be- 

 caufe the ufe of chains may in fome cafes be liable to ob- 

 jections. 

 An air-pump But I cannot avoid remarking that the moft fimple means of 



would be the gii a„d perhaps the bcA, on a fmall fcale, would be an air- 

 fimpleft organ. • 



pump fixed on the top of the cooler, and connected with the 



pump that fupplies the artificial refervoir. And though the 

 force required for extracting the rarified air, muft be in pro- 

 portion to the perpendicular height of the fyphon; yet it 

 cannot be more than what is required to raife a quantity of 

 water necetfary to fill the place of the air, as in the former 



3 apparatus 



