le-land, 7,215 ft. above sea level, across which it continues
northward 5 miles to the storage reservoir, which is on the north edge
of this elevated country. Hereafter, this reservoir will be called the
Nogal Reservoir, from the old mining village of Nogal lying 1-1/2 miles
to the north and 600 ft. below it. From this reservoir, the line drops
abruptly to the Carrizozo plain, and crosses the latter northward to
Coyote, at Mile 156, on the railway, at an elevation of 5,810 ft.,
passing, on the way, 6 miles east of Carrizozo, to which a branch pipe
runs, Carrizozo being 5,430 ft. above sea level. There is a
2,500,000-gal. reservoir at Coyote, and a similar one at Carrizozo.

[Illustration: FIG 1. MAP OF LINES OF EL PASO & SOUTHWESTERN SYSTEM]

This describes the gravity section of the line which brings the water
from the mountain stream to the railway. From Nogal Reservoir to the
latter, the capacity of the pipe is equal to the future daily
requirements; from the source of supply to the reservoir, the pipe has
twice as great a capacity, thereby storing surplus water. This section
is 32 miles long, with a 6-mile branch line.

The second, or pumping section, extends eastward along the railway,
rising from an elevation of 5,810 ft. at Coyote to 6,750 ft. on the Corona
summit, which is the water-shed line between the Rio Grande on the west
and the Rio Pecos on the east. At Coyote a pumping station lifts the
water to Luna Reservoir and the pumps at Mile 171, and the latter lift
it to the reservoir on Corona summit at Mile 192-1/2. This section is
36-1/2 miles long.

The third, or gravity section, extends from the reservoir on the Corona
summit to the Rio Pecos at Mile 272, dropping from an elevation of 6,750
to 4,570 ft. in 80 miles. The pipe line extends to Pastura, 58-1/2 miles
from Corona, as shown on Plate V.

Where the pipe line passes a water tank on the railway, a 4-in. branch
pipe is carried to the bottom of the tank and up to the top, where it is
capped by an automatic valve. A gate-valve is placed in the branch pipe
at its junction with the pipe line.

There are regulating, relief, check, blow-off, and air-valves,
air-chambers, and open stand-pipes on the line, too numerous to mention
in detail. They are designed to keep the wood pipe full, regulate flow,
prevent accumulation of pressure and water-hammer, and remove sediment.

_Water Pipe_.--A study of the profile developed a system of hydraulic
grades, p