Pierre weekly free press. (Pierre, S.D.) 1889-19??, 1912-12-26

That NJ because the geological forma-
| tfnn changes 80 frequently and sudden.
| " that no other effective treatment
has been found. So unstable II the
earth that the material In one part oe
the cut begins to move on an inclinA.
Ltion as low az n on owing to the
mass e stra Ned rock sliding over :
layer Of Ignite One slide now In nio-
ton, near the bridge Of Culebra, covers
an area Of 81 acres; from which 2,710.-
600 yards has already been removed.
leaving 500, 900 still TO be handled.
Then there is another little slide OF
no less than SO acres on the opposite
side Of the canal. The result Of these
earth movements, which are quite ex-
ceptional in engineering practice. has
been TO leave the canal In it, deepest
portions with very NAT slopes. The en-
couraging feature of the heavy work 1T
that point r. found In the statement
In the report that none Of the slides
which occurred during the year would
ships had the canal been In operation"
Appfepriatsd $32e,641, 4ta.
Already the appropriations made by
congress for the canal have run into
big figures, the total up to June 80,
last. being $293,561. 468, and since that
date there have been additional ap-
preparations. exclusive OF those for
making the grand total $322.541, 468. On
June 80, OF all these appropriations the
engineers had expended So per cent Of
the total estimated cost OF tho canal.
OF even greater interest, from an en-
gineering point Of view, than the vast
but commonplace work OF excavation In
sCulebra cut, was the work OF construct
ing the great locks at Gatun, Mira
flores and Pedro Miguel, for there many
novel problems have been solved and
lock machinery constructed OF special
designs Of q magnitude never before
heard
For instane, SO big are the valves at
the side OF the locks that a test showed
that It required pull OF over 10 tons
ON the stem to open one of these VAL
yes. All this work is done electrically,
and here, again, the engineers were
confronted with new difficulties.
Owing to the peculiar climatic condi-
tions oil the isthmus, with tropical
heat and extreme humidity. and the
deteriorating effect OF these conditions
on thu Insulation on electrical machine
cry, the ordinary insulation proved un-
reliable and the engineers found it
necessary to make great number Of
motors being pitted against one an
other
Operating Great Gatss.
It was q severe test for dynamo and
motor builders to have their machines
required to operate for period Of 10
days In building filled with steam at
tenaperatnre Of SO degrees centigrade
and having the motor cases filled with
water for five hours at 80 degrees But
finally the American motor builders
responded and suitable apparatus IL
being Installed.
Thus electric motors. under tests. are
now swinging the great gates OF the
canal. each Weighing very many tons
ard RS tall and broad as great sky
scraping building, in the remarkabie
time Of / minute and rs seconds In
cidentally. 1t appears that. to make
these gates. the iron workers must
drive and head s. 750,000 rivets.
The pivots Of these great locks are
being made OF a special grade OF steel
and bronze, not only for strength but
TO protect them against corrosion, q
very necessary precaution In view OF
the fact that they will always be SUBJ
merged in sea water after the canal ii
open. To guard against galvanic ac-
tion. zinc rings are also placed on the
bronze bushings. &
no supply the power TO operate the
gates and sluice valves In the locks,
Faftsl furnish current for the monster
electric locomC tiyes which are to tow
the steamships through the locks. q
great hydro electric station Is being
erected cdJacent to the spillway In
Gattiin dam .ai
The sanitation OF the isthmus also
mas been maintained ut the high level
SGT Sy Col. William G. Gorgas. the
chief ~ nitary officer, from the begin
ming. Contrary TO the common i'm,
preston the sanitary work, In the way
81 clearing land, does not extend ovsik
RGfA entire h1if f1rnv a ~