[ 73 ° ] 
Explanation of the Three Tables . 
The wheel A (Tab. 26 .), which is turned by the 
lever B (Tab. 2 7 *)j or rather moved up and down 
by it, is loofe on its arbor ; and likewife one of the 
lochets C (Tab. 26.), and the wheel next to it D. 
The outfide rochet E, and outfide wheel F 5 are fixed 
on the arbor. 
T here are two pinion-wheels G and El fixed on 
one arbor ; one on each fide, near the edge of the 
wheel A, moved by the lever. 
There are alfo two clicks a and b ; one a fixed to 
toe gieat«wheel A, the other b fixed to the frame. 
Thefe exclufive of the wheel I, that moves the pinion 
c y on the arbor of which, the crank d y and fly 
(Tab. 27.) are fixed. 
The effect is, when the lever B moves the wheel 
A downwards; its click a, forces the rochet E, fixed 
on the arbor K, to move along with it, and the other 
wheels the fame way. When it moves upwards, the 
click b fixed to the frame, flops the larger rocket C, 
and the wheel D next to it, which are pinned toge- 
ther ; and as the wheel A is carried upwards by the 
lever, the pinion G towards the edge of it, is forced 
round the wheel D, and moves the pinion H, on the 
other fide the great wheel A, which moves the wheel 
E fixed on the arbor K, the contrary way to the wheel 
A. By which means, the arbor K is conflantly turned 
the fame way, when the lever of the fire-engine moves 
either upwards, or downwards. 
The pinion G, by being made proportionally 
fmaller than the pinion H, keeps the arbor K in the 
fame 
