working at a time.

The pump building is a substantial concrete, brick, and steel structure,
50 by 80 ft. in plan, with a fire-wall, with two steel doors dividing
the floor space into an engine-room 50 by 50 ft., and a boiler-room 50
by 30 ft. A concrete coal-bin adjoins the exterior boiler-room door.
Coal is delivered directly from the car to the bin.

The plant is lighted by a small, but very complete, engine and dynamo on
one base and run by steam from the Sterling boilers.

The two plants are exactly alike throughout.

_Reservoir Leakage_.--The Nogal Reservoir basin is covered with from 2
to 5 ft. of good clay, except where it is punctured by a dike, or washed
down to the underlying sandstone by a few gullies. These punctures or
washes were covered or filled with clay from 1 to 4 ft. deep. During the
first season the leakage, above the 6-ft. contour, was at the rate of 2
in. per day.

As the water fell, due to leakage, evaporation, and use, a herd of from
300 to 400 cattle were worked around the shore line. This reduced the
leakage to 3/8 in. below 8 ft., and to nothing below 6 ft., above the
outlet. As the flow line rises higher each season, the puddling will be
continued to the top. The leakage at 12 ft. above the outlet, or 17 ft.
above the bottom, is still approximately 1 in. per day. The total
puddling, to date, covering two seasons, is equivalent to 11,150 days'
work of one cow, and covers an area of 1,500,000 sq. ft.

The clay packed densely, the final hoof marks being not more than 1/4