The record-union., 1895-04-13
LESSON IN HYDRAULIC MINING.

Our esteemed contemporary, the San
francisco CGlI, which, since it has passed
under the management and control of
Mr.. Shortridge, has manifested COM
mendable spirit of fairness in debate,
thinks the RECoRD-UNIoN is raising a
needless alarm concerning the menace of
hydraulic mining. Our contemporary is
somewhat removed from the scene of
action, and somewhat unfamiliar with
the history of hydraulic mining and its
effect upon the rivers, bays and valleys
Of California.
We confess to much pleasure that its
attention has been attracted to the sub
ject, because if it manifests that judicial
fairness toward this question which has
been characteristic of Mr.. Shortridge's
management of the Call, it is on the road
to speedy conclusions of very different
sort from those which it now processes.
It bases its criticisms of the RECORD
UNIONS statements upon the opinion
that no hydraulic mine can be legally
operated in the drainage basin of the San
Joaquin and Sacramento Rivers unless it
obtains a license from the Debris Com
mission. and that the law under which
that commission is operated expressly
stipulates that the tailings of such mine
must be impounded.
We submit to the considerate judgment
of our contemporary a series of facts
affording material out of which just con-
illusions may be formed.
Experiments have already been made
in impouading the mining detritus on an
extensive scale which were a failure
The experiment proved but one thing, TO
wit, that the amount of detritus was far
in excess of the estimate of the engineers.
When the detritus is once in the can
yons, ravines and beds Of the streams
the Debris Commission cannot restrain
it. The works constructed by the engi-
neers are swept away by floods. Bridges
holding certificates of proper construc-
tion according to the highest scientific
knowledge have not held to their moor
ings, but have gone down with the floods.
Engineering science, 80 called, is beset
with mistakes.
The Debris Commission has issued
lioennes to mine before the works neces-
zsry to restrain all the detrItus available
to be moved were constructed.
The Secretary Of War has transmitted the
report of the California Debris Commits
sion, transmitted by the engineers of that
commission, stating that the available
storage capacity constructed at the pres
ent time and for partially and wholly
completed operations in the future, is
S.5O0.0O0 cubic yards.
This is not statement that that capac-
ity has been constructed. 1t is partially
and wholly completed"
The Debris Commission has issued
licenses whore the allegation OF the
amount of earth available to be moved,
made by the miners themselves, is 61,-
0O0. 900 cubic yards. The engineers of
the Debris Commission state distinctly
that there is an estimated amount of sew
eral hundred million cubic yards availa-
bio to be worked.
The Debris Commission has issued Ii
censes to 1l2 hydraulic mines having in
contemplation the removal into the
streams of 6l,O0O, 600 cubic yards, with a
restraining capacity of S,5O0,00o cubic
yards.
It is wholly impracticable to regulate
the restraining capacity of dams to the
amount Of earth moved into the channels
of the streams
When our contemporary has duly
weighed the significance of the facts
herein presented; when it has reflected
that region of country now occupied by
over 100, 600 inhabitants is menaced with
destruction If the brush dams built to
hold back the result of a mud volcano
should burst; when it has recalled the
frequent instances of the breaking of
dams constructed according to the most
improved engineering plans and strictly
consistent with engineering science;
when it remembers the destruction in the
Conemaugh Valley. including the city OF
Johnstown, Pennsylvania. from the
breaking of dam, holding certificate
of security and scientific construction
from the best engineers of the age;
when it considers the recent instance
Of q stone dam giving way near