C 3*6 ] 
The running Water, being let in at the Top of 
the Funnel, falls thro' the Pipe upon E Ft he Stone 
in the Tub 5 it runs out at the Hole /, but cannot 
get off till it rifes as high as A . 
This raifes it in the Tubalmoft up to the Surface 
of the Stone, and it muft not rife higher. 
So much Water muft run in at the Top of the 
Funnel, as will keep it always full, or nearly fo. 
This Height of Water fqueezes it into the Pipe 
with a great Velocity; but, ftnce it pafl’es thro' the 
Throat of the Funnel, which is of a fmaller Bore 
than the Pipe, Room is left all round the Vein of 
Water for the Air to enter at the Air-Holes. 
It nofooner enters but it mixes with the Water, on 
the Account of the Rapidity of the Motion ; and 
both together make a white Froth, and intirely fill 
the Bore of the Pipe. When this Froth falls on the 
Stone in the Tub, it is dafhed into fmall Particles, 
which difengages the Air from the Water. The AiE 
cannot get out at P Q, the End of the Pipe, becaufe 
it is fid’d with the Froth, which falls with a great 
Force ; neither can it get out at the Hole /, becaufc 
the Surface of the Water is kept fo high above it,* 
and for that Reafon it rufhes out at N ; and if the 
Hole N be flopped, the Air will foon force all the 
Water in the Tub out at i, and then follow it. 
The moft convenient Way of regulating the Blaft, 
is to bore a fmall Hole in the Blaft-Pipe; and, by 
the Help of a Pin in it, to let out what Air there 
may be more than is wanted. 
The Dimenfions of fuch an Engine fufficiently big 
to fmelt harder Ore than any in Lead-Hills, arc fet 
down at the Bottom. 
Feet, 
