New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1898-08-13
EXPERIMENTS WITH AIR BAGS.
LIEUTENANT HOBSON SPENDS BUSY DAY
TESTING; APPARATUS FOR RAISING
St'NKEN VESSELS

Lieutenant Hobson spent nearly tho entire day
Yesterday on a wrccking barge and tug anchored
I'm the Bay of the Staten Island shore. making
tests Of rubber air bags and safety air valves IN
company with the representatives OF the manutact-
urers lie left the city about 10 o'clock yesterday
morning on the wrecking tug Hustler when ne
boar at Pier No. IS. Fast River. Accompanying
him were A. q, Delaney. representing the George
r Black Company. manufacturers OF compressed
air machinery: George II. r Schrader. representing
the manufacturers OF the Schrader safety Na!ve'
Milton A. Hudson. OF the Consolidated Safety Valve
Company. and G. +. Dodge. president OF the Hih-
eralzed Rubber Company.
Al the Merritt & Chapman Derrick and Wreck
ing Companys station. at Stapleton. staten Island
extensive preparations had been made for the ex-
periments on board the tug William Cooley and the
barge Henry Seymour. under the direction Of Cap
tain Charles y. Andrews. Of the wrecking COM
pany. Air pumps had been set up diving apparatus
had been prepared and three great anchors. weigh
ing I'm the aggregate q 800 pounds. had been dashed
together Lieutenant Hobson and the party boarded
the Cooley and shortly before noon 1t moved on,
into the Bay to point where the lead showed
twenty feet OF water. Luncheon was served on
board and the Lieutenant rowed ashore to tele-
nhone his regrets at being unable TO keep an APP
pointment nj . O'Clock.
There were two largo obong rubber bags on
board similar TO those which have been purchased
bv the Government to be used in raising the Girls
tobal Colon These bags arc placed In the hold OF
a sunken vessel and inflated under heavy air pres
sure under water When raised to the surface and
relieved from the water pressure they are liable
TO explode, permitting the vessel to sink The
safety valve is designed to release the air when
the pressure rises above that which the bag Is
calculated to stand. The bags used In the test
Yesterday had a capacity OF 400 cubic feet and
lifting power OF eight and one-half tons each.
one OF them was attached to the anchors and
after being partly inflated was swung over and
dropped to the bottom OF the Bay. To this bag no
safety valve was attached. and II was inflated
until the air pressure showed twenty-five pounds.
Johnson the diver made several descents, return
ing TO the surface at short intervals TO make re-
ports. after which he cut the rope which held the
bag 10 the anchors II shot to the surface clear
ing the water like a big fish, and then hoated with
the ud ho m bna expected IL % Explode
Tests OF the valves shipboard followed after
which a schrader safety valve was attached 10
tom with the anchors. Two rubber pipes led from
the vessel this bag. being at the connection
the air entered When the pressure reached TWEEN
showed only eighteen pounds. This was puzzng
the expermenters until small leak was FOUND
by the diver. The pressure Old not rise above e
going and a mass OF bubbles showed that the
valve was releasing the excess pressure ;.
out OF the water close to the side Of the barge
that the spectators were covered with spray II
a sharp report and the bag collapsed The repre-
sentative OF the safety valve company explained
that IT was never INTENDED that the bags should
no time to relieve the air pressure. In actual use
the vessels came to the surface slowly.
were abandoned with the understanding that they
would be, continued this morning, probably from
son who had taken an active and tireless part in
conducting the experiments. would not discuss