[ i66 ] 



* XXIX. Di-fcr'ipfion of a new Water Engine, invented hy 

 Dr. West, of the I/l ,nd of Jamaica *. 



X HE fcrevv-pipes a and b (fee Plate V, fig. i.) turn in 

 diflfereht tlirectious, and the area of the lower mutt be to 

 that of the upper in the invcrfc ratio of the perpendicular 

 hi'i:rhte!, and as much more as will be neceffary to overcome 

 the friction. The jiipe b ought to widen a little from below 

 upwards, in order to accommodate itfelf to the falling water. 



PVbrking of the Engine. 



The valve of the pipe a at its upper orifice c being opened, 

 (while the cup or bafon /'is fupplied by any ftream water, 

 a part of which is wiftied to be raifed to a higher elevation,) 

 the pipe a nuift be filled with water. It will. continue full, 

 ■tho;.irh its lovver orifice be open, if the valve fit clofe ; and, 

 water contiauinjj to be poured into the cup /from the pipe d, 

 if a motion on The axis be then communicated to the pipes 

 in a diredion oppofite to that of the Iteam ilTuing at e, the 

 whole will continue to move round fo long as vvaler is fupplied 

 bu the pipe d, and part of the water will afcend in a, and be 

 detivered into the upper circular gutter g, g. 



I 



XXX. Defcription of a new Hygrometer, 

 siE, To Mr. Tilloch, 



HEREWITH enclofe a fcbeme for an bygrometer, which 

 appears to me to be an itnprovement on the conmion (oat- 

 beard) hygrometer in feme refpefts, though, being more 

 complex, it is more likely to be out of order. 1 have made fc- 

 veral of them, and find they aft tolerably well. Should you 

 think the invention worth noticing in your publication, you 

 are welcome to make what ufeof the paper you think proper. 

 Two other kinds of hygrometers I have alfo made, but they 

 do not anlucr fo well as I think, with fome iinprovcment, 

 they might be made to do. In one the index moves under the 

 fpirals of a watch fpriug, bv which the number of revolutions 

 may be reckoned; on account of the (iiflVicfs of the llecl, the 

 index does not move with freedom. In the other the index 

 moves between the coils of a piece of paper cut in a fjiira! 

 form, on which paper are figures marked to regilter the place 



* Coinmunicatcd by Mr. Robcrtfon Buchannan, enginetr, Ginr<jo\v. 



it 



