Section 69.—RAISING AND LOWERING.
(See also [p. 148].)
[2396]. Richmond’s patent balance hydraulic lift. A is the lift cylinder, connected openly to the balance cylinder B, which is weighted to nearly balance ram A and cage. Pressure water is applied to ram C to raise the load in cage.
[2397]. Waygood’s patent hydraulic balance lift. A is the lift cylinder communicating with the interior of cylinder and ram B which are fixed; cylinder C and ram D are loaded to nearly balance the cage and ram A, and the load is raised by admitting pressure water to cylinder C.
[2398]. Lever and rack lifting motion. The rack may be held up at each lift by a pawl.
[2399]. Rack and lever suspended hoist. A pawl or brake may be added to sustain the load.
[2400]. Spanish windlass.
![[Larger plate.]](#3701448400155979539_plate142lg.png.id-9177013917935181784.wrap-0.html.html){kind=link}
[2401]. Double hoisting barrels, geared together; the rope passes round both barrels.
The “Otis” low pressure elevator (hydraulic) is worked from an overhead air accumulator at 80 lbs. pressure, the hydrostatic head being 40 lbs. There is one descending main pipe connected to a small tank or close vessel, into which the pumps deliver, and from which the lift pressure water is taken.