The chronicle=news., 1912-11-18

oil.iGS. On June 30 OF all these ap-
propriations. the engineers had ex-
pended 60 per cent Of the total es-
timated cost of the canal.
or even greater interest from an
engineering point of view. than the
vast hut commonplace work OF exca-
walton In Culebra Cut. was the work
of constructing the great locks at Ga
tun. and Miraflores. and Pedro Mig
uel. for there many novel problems
have been solved and lock machinery
constructed of special designs OF a
magnitude never before heard OF.
For Instance. 30 big are the valves
at the sides OF the locks that test
showed that IL required pull OF
over ten tons on the step open one
OF hcsc valves. All this work IL done
electrically. and here again tho en-
Eincers were confronted with new
difficulties. Owing 10 the peculiar
climatic conditions on the isthmus.
With tropical heat and extreme hu-
midity, and the detoriorating effect
of these conditions on the insulation
OF electrical machinery. the ordinary
Insulation proved unreliable. and the
engineers found II necessary to make
| n great number Of experiments. no
less than 10 sample motors being pit
ted against one another. II was an
awful test for dynamo ana motor
builders to have their machines re-
- fn ;
days In n building filled with steam
at temperature OF 90 degrees cen
tigrade md having tn. motor cases
filled with water for fiv. hours at 10
degrees. but finally the American
motor builders responded and suit
able apparatus IL being Installed.
Thus electric motors under tests.
are now swinging the great gates OF
the canal. each weighing very many
tons and as tall and broad as great
sky scrapinR building In the remark
able time Of one minute and forty
eiEh, seconds. Incidentally II APP
pears that to make these gates. the
iron workers must drive and head
s. 80 900 rivcts. The plvots of these
great locks are being made Of spe-
cial grade Of steel and bronze. not
cniy for strength. but 10 protect them
against corrosion. u 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 salranlc action.
zinc rings are also placed on the
bronze buxhinGs.
To supply the power TO operate the
gates and sluice valves in the locks
and furnish current for the monster
electric locomotives which are to tow
the steamships through the locks.
great hydro electric station Is being
erected adjacent to til. spillway In
Gatun dam. Their are three :.:ao
ki'owatt wasG- t1rb,nes. and three
1000 kilowatt gensrators with suit
able cxciters and other auxiiiaries.
There will be enough ayaiiabi. water
from the storage in Lake Gatun to
warrant the Installation Of 5000
kilowatts. though In the dry season
II will be necessary. to draw upon the
storage. Altogether II Is figured
cent OF the minimum water 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.
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 fortifica-
ton has also been progressing well.
nearly half a million yards OF con-
crete having been placed In the NOR
tar pits and gun emplacements dur
ing the last year. The sanitation OF
the 1sthmus also has been maintained
at the high level set by Col. William
lC. Georgas. the Chief Sanitary Ofiic-
/ er. from the beginning.
Contrary to the common impress
sion the sanitary work in the way OF
clearing land does not extend over
the entire zone but less than ZOO
OF the 27S,S4S acres In the tract are
kept clear for sanitary purposes and
almost the entire zone is In Its orig
inal condition as regards brush and
Jungle. ...