( 79 ) , 
and Funnels, by Brafs Ferrils and ‘Elbows, turning 
in all manner of Angles, Thefe are not.reprdentcd 
here. 
If the Velocity of the Water is very great, the Air 
will go even beyond the Eminence of the Pipe. 
, To let out the Air from the Gondud Pipes, which 
obflruds the Running of the Water, I recommend the 
Experiments which I made, and the Apparatus which 
I applied to a Wooden Condud Pipe of nine Inches 
Bore, which runs a Mile and an half from the Water 
Engine at Tork- Buildings to a Refervoir near Caven- 
di^lo-fquare the Surface of the Water in the Ciftern 
at the Water-houfe being fometimes 1 5, and fometimes 
20 Foot above the IfTue at the Refervoir. 
Upon a Part of the Pipe, fuch as A B (Fig. 9.) I 
fix’d a Leaden Pipe DTof 2 Inches in the Bore^ by 
means of 3 Ferrels, or fhort Communication-Pipes* the 
firft at D, juft beyond the Beginning of the Space CC, 
that us’d to be fill’d with Air in the running of the 
Water, the Second in the Middle of the Leaden Pipe, 
and the Third at the End of it ^ the Length of the 
Pipe itfelf being from 12 to 24 Feet, according to the 
Steepnefs of the Defcent, the fliorteff Pipe being fuf- 
ficient where the Defcent is very quick.From the Mid- 
dle of the Leaden Pipe above-mention’d (call’d a Ri- 
der, from its being laid along on the Main or Condud 
Pipe) there goes another Leaden Pipe as E of the 
fame Diameter, riling all the Way very gently from 
E to the Cock and fo on to /; becaufe, if there 
was the leaft Defcent,’ Water wou’d lodge in it. 
Now, when the Water runs from A to B, the firR 
Ferril D will catch the Air as it runs, fo as to let it 
out at /, if the Cock U be open, fometimes without 
going toG or to C. But if the Cock had not been open’d, 
till the had pafs’d thro’ the Part A B 0^ the 
Pipe, the At wou’d lodge in the Space CC, and be 
E 2 , cifcharg’d 
