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
trench.

At least 27 pieces of cracked pipe got past the field inspectors and
into the trench. This cracked pipe began blowing out at a pressure of 50
lb., and continued until the full normal pumping pressure was reached,
when the breaks suddenly ceased. These pipes were broken out at the rate
of 1 or 2 per day, with an occasional day between breaks. A 24-hour
work-train service was maintained. The pipe gang soon became skilled,
and could put in a new section of pipe in from 4 to 6 hours. Each break
generally caused an interruption of about 6 hours to the pumps on the