The midland journal. (Rising Sun, Md.) 1885-1947, 1895-02-01
DIGGING TUNNELS.
THE PRESSURE MEN BEAR WHILE
WORKING UNDER WATER.

Peculiar Sensations and Sometimes Fatal
Notwithstanding Through Water
Hole Under the Hudson River-Interest-
ing Talk with an Air Lock Worker.
Laboring on the firm earth, with "all
put of doors" to breathe, perspiring and
mayhap grumbling at ones hard luck,
o person seldom, if ever, stops to think
that men work day after day deep down
In the water or the mud, with none but
artificial light to guide their move
ments and only the air that is pumped
to breathe.
People who work in the open air
would have only to work for short
time in divers suit, caisson or an
air lock, getting taste Of what it is
like and how it feels, to be cured forev-
er of grumbling at their lot and to thank
their lucky stars that it has been Or
dained that they work on top of the
earth. The work Of a diver, his sensa-
tions while under water and his expert
enoes have often been written about,
but those Of the air lock and caisson
worker have not. While he does not
face the danger of fouling pipes and
lines, as does the diver, he stays down
longer, gets warmer, and his great dam
ger lies in the stagnation of blood and
paralysis, resulting from the change of
atmosphere.
Mr.. R. G. Rapier of East Cambridge
is an air lock worker and talks most in
terestingly. His work was mainly in the
air locks used in building the great Hud-
son river tunnel. To reporter he talk
ed of some of the sensations, dangers and
experiences. He said that, while man
working on the surface Of the earth
bears up an atmospheric pressure of 10
pounds to the inch, men in the locks
bear pressure Of from 15 to so pounds
Of compressed air, according to the
depth. The heaviest pressure ever work.
the Swedish coast-65 pounds Four Of
these died five minutes after coming out.
While as general thing the diver
stands not nearly that amount Of pres
sure and seldom stays down more than
two hours, the men in the Hudson river
tunnel stoo a pressure Of from 45 to
46h pounLs and worked in four hour
shifts Some men staid down 20 hours
at stretch, but did not work all the
time, and Superintendent Haskins once
staid down "a hours. The sensations
experienced are peculiar. When man
first steps in, there is a tingling in the
ears and pain in the head, and when
he talks it is apparently through the
nose. This is caused by the pressure,
and the remedy is to hold the nose.
close the mouth and blow against the
ears. This relieves the pain and stops
the sensation. When the pressure is all
on, the worker feels all right and expe-
riences no discomfort. Then there is q
sort of exhilaration, and a man does
more work in the lock than he could do
outside.
Another peculiar thing about the ao-
tion of the pressure is that a man may
have liquor enough aboard when out
side to just make him feel jolly, but
when he steps into the lock he is as
drunk as loon. The danger lies in
coming out of the pressure into the open
air; 1t is then that man is apt to suf-
fer from stagnation Of the blood and
paralysis. caused by the change Of at
mosphere. Besides this man may be
attacked in the head or stomach with
severe pains. Three out of five cases
where the head and stomach are attack
ed result fatally.
Another severe malady resulting from
the change is what is called the bends.
This is the air getting in between the
flesh and the bone. It is extremely pain
full and SO severe that quart of whisky
administered in half an hour would not
intoxicate the patient. The stagnation
and paralysis are the worst dangers
and do the work quickly. Many men
have been keeled over by these causes,
and not q few die. Old timers at the
business sometimes get caught. Mr..
Rapier himself was twice attacked.
The remedy for this paralysis is quick
return to the air lock. The effect of the
pressure varies on animals, as is shown
by the mules used in the Hudson river
tunnel. Some Of these beasts are kept
at work down below for year, and on
being brought up are worth more than
when they were taken down. Others
that had only been in the works four
months had to be killed.
The men as general thing do not
remain great many years at the busi-
ness, and man should never work at
1t after he is 40 years Of age. Cutting o
hole and building tunnel through wa
ter is an extremely difficult thing and
by many was thought to be impossible.
Still it was done in the case of the Hud-
son river tunnel, and the method, as
told by Mr.. Rapier, is very interesting.
The work on the tunnel had progressed
until body of water was struck. How
to tunnel through this hole of water
was puzzling question. Itwas done in
this way. A so called balloon was con-
structed by making netting Of wire
rope and covering this netting with can
vas. Tho interior of the balloon was
then filed with blue clay and salt hay.
When filled, the balloon, 80 feet in
diameter, weighed 140 tons. The hole
of water was then located, and with the
aid of huge steam derrick the balloon
was dropped into the hole. Then several
scowloads of dirt were dumped down
ON to the balloon, and the whole thing
was left to settle.
At the end of ten days the work Of
cutting through the balloon was begun.
This was very difficult job. An idea
of what hard cutting it was may be
gained from the fact that it took two
months to dig through the 80 feet. The