[ 102 ] 
in the manner of a diagonal fcale, upon the face 
of the rod H I. 
G L is the upper part of the rod of the pump, for 
drawing the water out of the lower ciftern, in 
order to raife and keep up the furface thereof 
at its defired height, in the head D E ; thereby 
to fupply the water, expended by the aperture 
of the 11 u ice. 
M M is the arch and handle for working the pump, 
which is limited in its ftroke by 
N a piece for hopping the handle from railing the 
pifton too high ; that alfo being prevented from 
going too low, by meeting the bottom of the 
barrel. 
O is the cylinder, upon which a cord winds, and 
which being conducted over the pullies P and 
raife s 
R, the fcale, into which the weights are put, for 
trying the power of the water. 
S T the two flandards, which fupport the wheel, 
are made to Hide up and down, m order to ad- 
juft the wheel, as near as poflible, to the floor 
of the conduit. 
W the beam which fupports the fcale and pul- 
lies ; this is reprefented as but little higher than 
the machine, for the fake of bringing the figure 
into a moderate compafs, but in reality is placed 
iy or 1 6 feet higher than the wheel. 
Plate V. Fig. a. is a fedtion of the fame machine, 
wherein the fame parts are marked with the fame 
letters as in Fig. i. Belides which 
X X is the pump barrel, being 5 inches diameter, 
and 1 1 inches long. 
Y is 
