8-inch nozzle; three ropes are used from
the wheel shaft to the counter-shaft, and six ropes from the latter to the
fly-wheel shaft.

[Footnote 5: The revolutions per minute, of these wheels, as here given,
are only approximate, as the design was to have the bucket speed=1/2
2(gh)^{1/2}.]

For driving the pumps, there are two water-wheels, set on the same shaft,
one 5 feet and the other 7 feet in diameter, either of which can be used
at will, thus permitting different rates of speed; two nozzles are placed
on each wheel, so that if necessary the power can at any time be doubled.
The smaller wheel has a 1-1/4 inch nozzle, and runs 360 turns a minute;
the larger has 1-1/8-inch nozzle, and makes 270 turns a minute. There are
two ropes from the wheel-shaft to a counter-shaft, and four ropes to the
fly-wheel shaft, on which is the pinion driving the spur-wheel attached to
the pitman of the pump-bob. Hoisting is done by two wheels placed side by
side on the same shaft, the buckets and nozzle of each wheel being placed
in opposite directions. Both wheels are 8 feet in diameter, with
15/16-inch nozzles, and make at full speed about 225 turns a minute.
Reversing the movement of the shaft is done by shutting off water from one
wheel, and turning water on the other wheel; the two water-gates for these
nozzles are quickly opened or closed by hydrostatic pressure, afforded
from the water main. In addition to the usual brakes on the winding-reels,
a brake is placed on the wheel-shaft, so that it can be stopped in a very
short period of time.

The shock to the pipe by the almost instantaneous cutting off the water at
these hoisting-wheels (nearly one cubic foot per second) has not
apparently had any injurious, effect. To lessen this shock, a compensating
balance was designed, but which is not now in use. A wheel, of small
diameter, is used for the smithy, etc., running at a very high velocity.
The wheel driving the stamp-mill is 6 feet in diameter, makes 300
revolutions a minute, and is supplied through a 1-3/16 inch nozzle. The
head of water at this point is a few feet greater than at the other
wheels. Power is transmitted from the hoisting and mill-wheel shafts by
two and four ropes, the same as with the pumping rig. The amount of work
done, or of water used, has not been carefully determined; judging from
the indicator cards taken from the old steam-engines, the managers of the
Idaho believe that an efficiency of fully 80 per cen