II. A Defcription of the Water-Works at Lon- 
don-Bridge, explaining the Draught of Tab. I. 
(By H. Beighton, F $. 
HE Wheels are placed under the Arches of 
London-Bridge r and moved . by the common 
Stream of the Tide-Water of the River Thames. 
AB the Axle-tree of the Water- Wheel, 19 Feet 
long, 3 Feet Diameter* in which C,D, E, F, are four 
Sets of Arms, eight in each Place, on which are fixed 
GGGG, four Rings, or Sets of Felloes, in Diameter 
20 Feet, and the Floats H H H, 14 Feet long and 18 
Inches deep, being about 2 6 in Number. 
The Wheel lies with its two Gudgeons, or Centers, 
A B, upon two Braffes in the Pieces M N, which are 
two great Levers, whofe Fulcrum, or Prop, is an 
arched Piece of Timber L, the Levers being made 
circular on their lower Sides to an Arch of the Radius 
M O, and kept in their Places by two arching Studs 
fixed in the Stock L, through two Mortifes in the Le- 
ver M N. 
The Wheel is, by thefe Levers, made to rife and 
fall with the Tide, which is performed in this Manner, 
The Levers MN are 16 Feet long ; from M, the Ful- 
crum of the Lever, to O the Gudgeon of the Water- 
Wheel, 6 Feet ; and from O to the Arch at N, 10. 
Feet. To the Bottom of the Arch N is fixed a ftrong 
triple Chain P, made after the Falhion of a Watch- 
Chain, but the Links arched to 3 Circle of one Foot 
Diameter,, 
