Ottumwa tri-weekly courier. [volume] (Ottumwa, Iowa) 1903-1916, 1912-11-19
oTTUMWA COURIER. TUESDAY, NOVEMBER 49, 1912.

the statement in the report that none
OF the slides which occurred during
the years would have interfered with
the passage of ships had the canal
been in operation"
Cost Is Very Great.
Already the appropriations made by
congress for the canal have run into
big figures, the total up to June 80
last. being 1898, SCI, 46S, and since that
date there have been additional appro.
priations, exclusive of those for fortt
fications, amounting to $2S,980, 000,
making the grand total $322,541, 46s.
On June 80 of all these appropria.
tions, the engineers had expended
sixty-nine per cent Of the total esti
mated cost Of the canal.
| Electrical Experiments.
OF even greater interest from an en-.
gineering point of view, than the vast
but commonplace work of excavation
In Culebra Cut, was the work of con-
| structing the great locks at Gatum,
and Miraflores, and Pedro Miguel. for
their many novel problems have been
solved, and lock machinery con-
structed of special designs of magni-
tude never before heard, of. For In.
stance, so big are the valves at the
side Of the locks that test showed
that it required pull Of over ten
tons on the stem to open one of these
valves. All this work is done electric
ally, and here again the engineers
were confronted with new difficulties.
Owing to the peculiar climatic condi-
lions on the isthmus, with tropical
heat and extreme humidity, and the
deteriorating effect of these conditions
on the insulation of electrical ma
chinery. the ordinary insulation proved
unreliable, and the engineers found 1t
necessary to make a great number OF
experiments, no less than sixteen
sample motors being pitted against
one another. 1t was an awful test for
dynamo and motor builders to have
their machines required to operate
for period Of ten days in building
filled with steam at temperature of
so degrees centigrade and having the
motor cases filed with water for five
hours at 80 degrees. But finally the
American motor builders responded
and suitable apparatus is being IN
stalled.
Millions of Rvets Used.
incidentally it appears that to make +!
these gates, the iron workers must
drive and head 5.750,000 rivets. The !
pivots Of these great locks are being |
made of special grade Of steel and
bronze. not only for strength. but to
protect them against corrosion, a
very necessary precaution in view OF
the fact that they will always be
submerged in sea water after the canal
is open. To guard against galvanic &C.
fiN11 n a nl9rnf
bronze bushings.
Huge Power Plant Needed.
To supply the power to operate the
gates and suffice valves in the locks,
and furnish current for the monster
electric locomotives which are to tow
the steamships through the locks, a /
erected adjacent to the spillway in
watt water turbines, and three 1000
kilowatt generators with suitable ey-
citers and other auxiliaries. There will
be enough water from the storage in
Lake Gatun to warrant the installa-
ton of 5000 kilowatts, though in the
dry season it will be necessary to
draw upon the storage. Altogether 1t
Is figured that for this electric work
1 per cent Ol Tie ullulllluul NoICA
system Of the canal will be required.
A part Of the electricity is to be used
for lighting the line of the canal.
There will be concrete lamp posts
100 feet apart throughout the entire
length of each lock wall. Altogether
1000 lamps will be installed at the
locks.
Work Generally Rapid.
Outside of the canal proper the re-
port shows that work has been going
on rapidly in preparing harbors for
the shelter of ships at each end Of the
waterway. The work of fertilization
has also been progressing we'll, nearly
half million yards Of concrete hav-
ing been placed In the motar pits and
gun emplacements during the last
year. The sanitation of the Isthmus
also has been maintained at the high
level set by Col. William c. Georges.
the chief sanitary officer, from the be-
ginning.
Contrary to the common impression
the sanitary work in the way of clear-
Ing land, does not extend over the en-
tire zone but less than 1900 Of the
27S,S48 acres in the tract are kept
clear for sanitary purposes and al
most the entire zone is in it's original
condition as regards brush and