From Coyote, east along the railway, the wood pipe is remarkably tight.
The rate of leakage from it, as determined by 600 observations uniformly
distributed, was as follows:


11-in. pipe = 120 gal. per mile per day.
8-1/2 and 7-1/2-in. pipe = 268 " " " " "


The maximum rate on 1 mile was 1,613 gal. The minimum found was zero.

The observations were made by uncovering a joint and measuring the
leakage therefrom for 10 min. A graduated glass measuring to drams was
used. The rate of leakage varied from 5 drops to 45 oz. in 10 min. Of
the joints uncovered 57% was found to be leaking. It is rather
remarkable that, in the large leakage of the 11-and 12-in. pipe between
Coyote and Bonito, only one out of every eight joints was leaking. This
indicates a physical defect in such joints. The largest leak found on
one joint was at the rate of 17[,?]280 gal. per day. Leakage between or
through the staves is not measurable, as it is not fast enough to come
away in drops unless there is some imperfection in the wood.

The insignificant leakage of 120 gal., stated above, is from the 11-in.
pipe in the pumping main between Coyote and Corona. The present maximum
working pressure on it is 100 lb. per sq. in. All the figures given
above include visible and invisible leakage, the latter being such as
does not appear on the surface. The visible leakage is but a small part
of the total.