The National tribune., 1905-11-30
SCIENCE AND INVENTION.
Work of the Worlds Busy Brains in Discovering nvenng and
Creating.
SANITATION OF THE CANAL ZONE.

SANITATION OF THE CANAL ZONE.
Col. William C. Gorgas, U. S. A, who
is the Chief Sanitary Officer of the Ca
nal Zone, reported to the Smithsonian
Institution that the problem before him
is to protect $1,000 men who are to
be employed on the canal from yellow
fever and malaria. Yellow fever is not
endemic on the Isthmus, but had to be
imported. When an infected person is
brought in one of the Stegomyia mos
quitoes must bite him and start the in
lection in the country. The first thing,
therefore, is to keep men suffering
from yellow fever from landing and the
next thing is to get rid of the Stego-
myia The latter is a house mosquito.
and never travels far from her birth
place She affects principally clean
rain water barrels and other recepta-
cles of household water. Wherever a
case of yellow fever occurs the house
must be fumigated SO effectually as to
destroy all the mosquitoes. The same
must be done with the houses immedi-
ately around, so as to completely break
UP what is termed 1.-The focus" Every
receptacle for water must be screened
to keep out the mosquitoes, and the
safest way is to have the water brought
in pipes from distance, so that there
is no need of any standing water This
was the process by which the yellow
fever was stamped out at Havana.
The next, and even more important
problem, is the elimination of malaria.
There are 10000 natives in the district
in about 90 small villages, and these
are nearly all infected by malaria, so
that if mosquito bites one of them
she usually infects one or more of the
Iaborers who have been brought to do
the work. This was what destroyed
the laborers which the French Com
pany imported.
The remedy is to destroy the mos
quitoes and induce the natives to take
enough quinine to kill the fever germs
in their blood. In getting rid of the
mosquito the yards have to be cleaned
up and also the surfaces of the roads,
50 there will be no puddles. Where
these latter cannot be gotten rid of
their surfaces are kept covered with
be done effectively and the malaria
wiped out in the whole zone.
GUN EROSION.
The making of great guns still con-
tnues to be exceedingly embarrassed
by the severe scoring or erosion which
follows the use of high explosives and
the gaining of long ranges with great
penetrating power. After cannon has
been fired a certain number of times
with a high explosive the inside of the
barrel looks like clay over which a
rapid stream Of water has run for some
time. There are various theories to ac-
count for this. One is that the intense
pressure disintegrates the fiber of the
gun, destroying the molecular force
which holds the particles together and
converting them into powder. Another
is that the force of the explosion act
ually tears out the gun the same as a
blast of wind will score a hillside or as
water will erode a bank. Another the
DRY is that the white-hot gases melt
away the metal as a block of ice is
melted in a jet of steam. Whatever
the theoretic action the rifiing is
burnt out, the shell will not rotate, and
begins to tumble end over end. The
builders of these guns have overcome
every other difficulty except this one.
which is as obstinately puzzling as ever.
Various expedients have been tried, but
X seems inevitable that nature will de-
mand her price for results secured. and
that IL high velocity and great pene-
trating power are secured it must be
at the expense of the structure of the
gun and the shortening Of the wea-
pon's life. AT the gun tests at Sandy
Hook muzzle velocity was obtained
ranging from 1913 feet per second to
$3.50 feet, but the pressure ranged
from 1924 pounds per square inch to
1870 pounds. The guns stood these
incredible pressures very well. except
for the erosion of the inner tubes, and
this was so great as to indicate the
rapid shortening of the guns life. So
far no effective remedy has been sug-
gested.