The Water Supply of the El Paso and Southwestern Railway from Carrizozo to Santa Rosa, N. Mex. | Page 9

by observation the relative velocities in the two pipes, as above
deduced.
_Test No. 2_.--To determine these points, a second test was made, on
March 31st, 1908, twenty days after the first one. In this test, green
aniline, red potassium permanganate, and bran were used. An observer
was placed at the end of the 10-in. line at B (Fig. 2), and, by letting a
small quantity of water run from a relief-valve there, he was able to
note the time of the appearance of the colors and the bran.

The green was started in the upper end of the 10-in. pipe, at A (Fig. 2),
at 8.30 A.M. It appeared at B in 22 min., and at E in 3 hours and 52
min.
The red was started at 8.45 A.M. It reached B in 21-1/2 min., but it was
so faded that the time of its appearance at E could not be noted exactly.
The bran was started at 9.00 A.M. It reached B in 22 min., and
appeared at E in 3 hours and 51 min.
From the average of these figures, the velocities were:
In the 16-in. pipe, 3.792 ft. per sec. " " 10 " " 9.695 " " "
and the discharges were:
In the 10-in. pipe, 5.287 cu. ft. per sec. " " 16 " " 5.293 " " " "
The application of the equation for equalized relative velocities, as in
the first test, gives:
Velocity in 16-in. pipe = 9.705 " " 10 " " = 3.791 Discharge of 16 " " =
5.292 " " 10 " " = 5.293
These last figures would check exactly, except for dropping figures in
the fourth decimal place.
The results of these two tests, considering that 20 days elapsed between
them, are in very close agreement, and establish the fact that bran is an
accurate medium of measurement.
_Test No 3_.--The 500 ft. of 10-in. pipe in the 16-in. line near the
reservoir (Fig. 2) were replaced by 16-in. pipe in the summer of 1908.
On May 12th, 1909, green aniline was started through the pipe at A at
11.00 A.M., 11.30 A.M., and 12.00 P.M. In each case it appeared at E
in 3 hours and 31 min. This time is 20 min. less than that observed in
the tests of the previous year, and is due to the removal of the 10-in.
pipe from the 16-in. line and to the increasing smoothness of the

interior surface of the pipe.
The relative velocities and discharges under the third test, using the
nomenclature of the first and correcting the lengths of pipe on account
of the removal of the 10-in. pipe near the reservoir, are:
48,000 + 12,700 ----- --------- = 12,660 x 2.56x x = 4.183
and 2.56x = 10.708
and the discharges are:
From the 10-in. pipe = 5.840 cu. ft. per sec. " " 16 " " = 5.839 " " " "
Coefficients.--On May 12th, 1909, the 10-in. line was working on a
grade of 0.03338, and, with n = 0.009, C should have been 131. It was
actually 138, making n = 0.00866. The 16-in. line was working on a
grade of 0.0030625, and, with n = 0.009, C should have been 145. It
was actually 141, making n = 0.0092.
Referring to the estimated hydraulic grade between Coyote and Corona
(Plate V), the coefficients, 0.01 and 0.012, were used for wood and iron,
respectively, on which basis, the maximum pressure at Coyote was
expected to be 304 lb. and, at Luna, 310 lb. per sq. in. The actual
maximum at Coyote, with pumps at full normal speed, was 270 lb., and,
at Luna, 278 lb., indicating that the values of the coefficients taken
were too high. This checks with the tests between Bonito and Nogal.
Of course, the iron pipe will increase in roughness, and, in time the
pumping pressure will approach the calculated amount. The interior of
the iron pipe now has a smooth coat of asphalt.
Pipe Breakage.--The breakage or damage to the wood pipe in shipment
occurred on the ends, the tenons being most exposed to injury from
shifting in the cars. The damage due to the shipment and handling of
the Elmira pipe was 1% and one-half as much for the Bay City pipe.
Less than 6 pieces out of 100,000 laid have had to be removed from the
trench.

The iron pipe came from Chattanooga, and was badly handled in transit.
Much of it was transferred en route, and 6% was broken when received.
The breaks were generally cracks of the spigot end. Of this broken pipe,
practically all was cut and laid. The average cut was about 16 in. from
the spigot end of 533 pieces. This cut pipe has caused no trouble in the