Return to Frequently
Asked Questions page. 
Return to Frequently
Asked Questions page. (Lecture delivered to the Harvard
Engineering Society on 6 Oct. 1939)
The U.S.S. Squalus [SS-192], the newest model of submarine,
while engaged in preliminary trials, sunk in 243 feet of water
off the Isles of Shoals in North Atlantic waters on 23 May 1939.
On 24 May, the living survivors, 33 in number were rescued, uninjured
and healthy. As the sun was setting on September 13, 1939, a solemn
procession of ships with colors at half mast let by the [Fleet
Tug No.26] U.S.S. Wandank, steamed slowly into the Portsmouth,
N.H. Navy Yard, with the stricken ship and the bodies of those
who lost their lives.
Those were, briefly, the high lights of the concluding chapter
of the story of 12 years of research and training by the Navy
after the tragic loss of the S-4 [SS-109] in 1927. In the
33 survivors, the Navy paid a "dividend" on the time
and money spent in preparedness.
In the Experimental Diving Unit at the Navy Yard, Washington,
on the morning of 23 May, one of the divers had just emerged from
the recompression chamber after having subjected himself to a
test which was to be the final check of a long series of tests
which established a new conception of decompression for divers.
I remarked to Dr. Willmon that this was the final "spot"
on the curve, and to be careful of the samples. The samples were
never run. A telephone call from Commander Lockwood in Operations
of the Navy Department said briefly these grim words "Squalus
is down off Isles of Shoals, depth between 200 and 400 feet, have
your divers and equipment ready to leave immediately." Within
2 hours the first group was in the air and speeding toward Portsmouth,
N.H. By midnight the 5 officers and 20 enlisted men had arrived
at the scene of the accident.
I shall never be able to record the various thoughts that flashed
through my mind during that 150 mile an hour ride through the
air to Portsmouth. My memory went back to the first lung experiments,
thrills of ten years ago, to the long and tedious years spent
in training submarine officers and enlisted men of the submarine
service to use the lung; to the first diving bell, the cranky
open bell that would dump and fall and half drown us if we were
not careful, of the final design produced by Commander Allen R.
McCann and the comfort that it was to operate. I recalled the
hundreds of thrills encountered in training and developing this
device. The dreaded hour was here! Would the dreams of the experimenter
come true or would some quirk of fate cross up the plans and thus
destroy all of this work? How many shipmates were waiting for
the answer? What were they thinking? Were they too deep? Would
the crude helium apparatus work if they were too deep for air
diving. Dr. Behnke, who was riding with me in the plane remarked
"I have a feeling that we'll do it." Inwardly I felt
the same way.
Upon arrival on the scene I reported to Rear Admiral Cyrus W.
Cole, the Commandant of the Navy Yard, Portsmouth, N.H., who was
in charge at the scene of the accident. He was in the Sculpin
[SS-191], a sister ship of the Squalus. The wind was blowing
briskly and the seas were choppy. It was nearly midnight. After
giving me the facts of the situation, he said "I will appoint
you to take charge of the diving operations."
The Squalus was lying in 243 feet of water, slight list
to port, down by the stern a few degrees. She was flooded aft
up to the control room, which meant the after battery compartment,
forward engine room, after engine room and after torpedo room
were probably flooded.
Thirty-three of her crew were alive in the forward compartments,
but all telephones to the after compartments were silent. The
Squalus had dived about 9 a.m., on the 23rd. After leveling
off at periscope depth a sudden rush of air was felt an immediately
after, water was observed to be pouring in through the engine
induction lines. Attempts to surface the submarine failed and
the stern sunk out of control. When at an angle of nearly 60 degrees
she hit bottom, the bow settled down to rest. The marker buoy
in the forward torpedo room was released and picked up by the
SCULPIN. The telephone in the marker buoy was manned.
While the Captain of the Sculpin, Lt.Cdr. Wilkin was talking
to the Captain of the Squalus, Lieutenant Naquin, the cable
parted and conversation had to be continued by the laborious process
of hammering code signals on the hull. Obviously the power system
had failed which meant that some sea water had leaked into the
forward battery. This introduced the danger of chlorine gas. It
was later learned that this was true, and that lungs were broken
out and distributed to all survivors, for protection against gas
and for escape if such action was decided upon.
The Captain reported all hands comfortable, but cold; pressure
in the compartments was about 12.5 pounds above atmospheric; hand
lanterns were being used for light, air clear of chlorine gas
and excessive CO2 in the control room and torpedo room; battery
compartment closed off except for the passage - (It lies between
the other two).
The U.S.S. Falcon [ASR-2], one of the Navy Rescue vessels,
Lieutenant G.A. Sharp, USN, commanding, was on her way from New
London with the rescue chamber and would arrive shortly after
daybreak on the 24th.
We told the Captain of the Squalus to rest as easily as
possible, that the pressure in the compartments would not injure
the men and that the Falcon would arrive about 6 am with
the rescue chamber.
We kept in contact with Lt. Naquin, bearing in mind that delay
meant danger if escape by use of "lungs" must be attempted.
Escape by this means would become necessary if some developments
made it dangerous for the men to remain in the compartments. This
was a delicate situation, for delay in attempting escape might
reduce the chances for successful operation of the lung because
of the reduced strength of the men caused by gas, exposure, lack
of sleep, and hunger. On the other hand, rescue by the rescue
chamber is safer, and there is less chance of losing men.
Wind and sea were increasing, but when the Falcon arrived,
four anchors were dropped in a square about 1500 feet on a side
and she was moored in the center near the location of the Squalus.
Some difficulty was experienced in getting the Falcon in
position because of the dragging of the windward anchors. She
was finally hauled as near to the correct position as we dared
about noon and rescue operations commenced.
During the previous night the wreck had been snagged with a grapnel
[grapple] by the [harbor tug] Penacook [YT-6] and it was
the line to this grapnel (21 thread manila) that was used for
sending down our first diver. We were not sure that the grapnel
was attached to the wreck and if it was attached just where it
might be located. This was worse than drawing to an inside straight.
My first diver was a second class Boatswain's Mate on the Falcon,
Sibitzky, over six feet tall and about 200 pounds of the Navy's
best brawn. We dressed him in his 200 pounds of equipment and
sent him down. Lady Luck smiled on us for he landed on deck and
excitedly reported "I see the capstan." What more could
we ask for? Our diver was within 6 feet of the hatch that we wanted
to get into. We had filled that inside straight. He reported that
the broken cable of the marker buoy lay across the hatch. This,
he was able to move clear.
I must digress momentarily to explain that the forward and after
hatches of our submarines are fitted for attaching the rescue
chamber. They have a flat doughnut shaped plate welded to the
hatch combing upon which the bottom of the chamber rests and a
bail over the center of the hatch to which the haul down wire
must be attached by the diver.
We made ready the end of the downhaul wire and slid it down the
descending line to the diver. He got the end and promptly lost
it so that we had to haul it up again and send it down a second
time. This time he shackled it into the bail and was ready to
come up.
Eleven years ago (1928) the first diving bells for rescuing men
from submarines were designed by the Bureau of Construction and
Repair, Navy Department. A curious quirk of circumstances led
up to this incident. While in command of the submarine S-1
[SS-105], in 1926, I wrote to the Bureau of Construction and Repair
and recommended the adoption of a diving bell for the purposes
of rescuing entrapped personnel from submarines. The S-1
carried the only submarine airplane hanger in the Navy and I completed
tests with a new type of plane during my tours of duty. This hanger
was a tank 20 feet long and 6 feet in diameter. When I was relieved
of command of the S-1, I went to the Navy Department, Bureau
of Construction and Repair, for duty in the Submarine section.
There I found my letter about the diving bell, unanswered. A short
time later I handled a letter from the new commanding officer
of the S-1, stating that the airplane tank was of no further
use, requesting authority to remove it, and requesting disposition.
I felt opportunity knocking and prepared a reply to send it to
New York there to be cut in half and used to make two diving bells
for experimental purposes.
In the meantime the S-4 was lost with all hands and the
Navy was very much "on the spot" because of the loss
of lives that might have been saved. The pressure of this incident
forced favorable action on the diving bell project. After nearly
two years of experimentation full of highly interesting results,
the final bell was evolved and christened a "rescue chamber."
Upon completion of two years ashore in the Bureau, I was sent
to sea in the reconditioned S-4 to carry out practical
experiments and training with the rescue chambers for all of our
rescue vessels. In the meantime, I had been perfecting the lung
for individual escape and the training of submarine personnel
in its use went hand in hand with the training of personnel to
handle the rescue chambers. The development of the lung is a long
story and will have to be told at some other time.
I have left the survivors waiting, but felt that some background
for the introduction of the now famous rescue chamber was needed.
This apparatus is a pear shaped steel chamber, the big end uppermost,
seven feet at the greatest diameter and ten feet high. It is divided
into an upper closed compartment and a lower open compartment
by a horizontal bulkhead which has a water tight hatch in its
middle. Surrounding the lower compartment is a ballast tank of
a capacity just equal to that of the lower compartment. Inside
the lower compartment is a reel with 400 feet of ½"
steel wire on it. The reel is operated by a shaft leading into
the upper compartment. The shaft is rotated by an air motor. On
the bottom edge of the lower compartment a rubber gasket is embedded
into a circular groove, so that when the chamber is brought into
contact with a flat surface (the hatch ring) a water tight joint
may be effected with the application of pressure. Attached to
the upper compartment is an air supply and an atmospheric exhaust
hose, wire wound for strength. Also electric cables for telephone
and light are attached. A wire pendant for hoisting and lowering
is shackled into a padeye on top. This wire is also used for retrieving
the chamber in case of emergency.
To return to the rescue operations, two experienced operators,
Harmon and Mihalowski, both divers from the Falcon entered
the upper compartment and the chamber was lowered over the side.
The end of the haul down wire had been unreeled and attached to
the hatch by Sibitzky. With the lower compartment flooded, the
ballast tank full and auxiliary cans full of water, the chamber
floated with several hundred pounds of positive buoyancy. The
auxiliary cans, 14 in number are carried in the upper compartment
and are dumped as passengers enter so that the proper buoyancy
will be maintained. Extra blankets, flashlight, hot soup, sandwiches
and extra CO2 absorbent were taken aboard for delivery to the
submarine.
Harmon reported ready and I told him to go down. He turned on
the air motor and as the wire was taken in on the reel the chamber
crept along the surface about one hundred feet from the point
where it was lowered into the water. Then it gradually submerged
looking like some sea monster as it sank from sight. Progress
was reported continuously until finally the report "Hatch
is in sight." Taking it slowly they hauled the chamber down
until it was resting on the flat seat surrounding the hatch. The
wire leading through a centrally located fair lead to the hatch
bail, also centrally located, causes the gasket to come into contact
with the seat evenly. The ballast tank is then flooded from sea
and the lower compartment emptied by admitting compressed air.
The seal of the gasket to the hatch is then accomplished by suddenly
releasing the compressed air in the lower compartment through
the hose leading to the atmosphere. Harmon reported the seal made
and the hatch leading to the lower compartment opened. Bear in
mind that the upper compartment is under atmospheric pressure.
Thus the sea pressure exerts an enormous pressure on the gasket
and the joint is absolutely watertight. The seating pressure in
this case was about 175 tons. Four steel bolts were then attached
to the hatch rings as a safety measure and the submarine hatch
was opened. This was opened slowly so that such pressure that
was in the submarine could be equalized with that in the chamber.
Each move could be followed by listening on the telephone. When
the submarine hatch was finally opened the dull thud of the hatch
falling open was a thrill I cannot describe. Not a shout or cheer
came over the phone. A few "wise cracks" such as "why
the delay," "where in the hell are the napkins."
The men had been trained and this was just like a drill. I ordered
them to dump 1000 pounds of water from the auxiliary cans and
load seven passengers. I wanted to make four trips, 7, 8, 9 and
9 in order to bring up the 33 survivors. I wanted to see how she
carried the load with each trip, so planned on increasing the
number by 1 each trip.
Harmon reported 7 passengers loaded, designated by the submarine's
skipper, Lieutenant Naquin. Next he reported "hatch closed"
and "ready to come up." I ordered him to "unbolt,
flood lower compartment, and blow the ballast tank". This
done, he reported "Seal broken, coming up." The air
motor, in reverse, unreeling wire, chugged away and there gradually
rising to the surface by its own buoyancy came the first load
of lucky men, almost a routine drill for us but in the eyes of
the outside world a miracle. We tried to appear calm and maybe
others were but to me this was the most exciting moment of my
life. 11 years of preparation, combating skepticism and constructing
imaginary disasters, all telescoped into one moment, who could
remain calm?
The chamber appeared first a green splotch beneath the surface
then the war color and she was hauled alongside. The top hatch
was opened and the 7 lucky men removed. I changed the operators
for each trip.
Soon the second trip was made, and when the chamber returned to
the surface with eight passengers it looked so heavy that I felt
that it would not be safe to carry nine on the third trip. This
was a blow for each trip meant greater risk; the weather might
get too rough, the anchors drag - in fact any one of a dozen things
might happen. However, it looked risky and I made my decision.
Five trips I announced, and told Lt. Naquin to send up 8 in the
third trip.
They were loading the 3rd bunch when Commander Sackett rushed
aft to tell me that by mistake 9 men had been brought up in the
2nd trip. I felt a genuine relief and immediately told Naquin
to send 9 the 3rd trip, leaving 8 for that eventful 4th trip.
How fortunate this was, we did not realize at the time. The 4th
trip was made to the bottom. The last eight including the Captain,
traditionally the last to leave his ship, were loaded. All were
secured and the return trip started. All of a sudden she stopped!
McDonald, the operator said "The wire is jammed on the reel."
Loose turns had allowed the hauling part of the wire to slip between
the turns on the reel and jam. This emergency had been provided
for and I told him we would heave on the retrieving wire and help
clear it. While hauling on this wire, it started to strand, strands
parted like fire crackers. We stopped hauling just before the
last strand parted. This emergency had not been provided for.
It was almost dark by now and the wind and sea were no better.
In order to save what wire was left I told McDonald to flood his
ballast tank slowly and I would lower the chamber to the bottom.
This was done and fortunately there was enough slack in the downhaul
wire to permit the chamber to reach the ocean bottom without turning
over. It was necessary to send down a diver to detach the haul
down wire from the hatch bail. Squire, a big 200 pounder from
the Experimental Diving Unit at Washington was designated to do
this. He was dressed, went down in the dark and reported that
the wire was too taught to unshackle. We had to send him a pair
of wire cutters. With these he cut the wire. This was a fine job
and could have been done only by an expert diver and one who has
lots of power in his arms.
The next step was to attach a new retrieving wire to the chamber.
Duncan and then Clayton attempted to take a new wire down, but
the darkness proved to be too much of a handicap. We used a lamp,
but the extra cable fouled and we found ourselves in a serious
situation with a diver fouled in the wire, the most dangerous
kind of fouling in the diving business. We finally managed to
get Clayton up and then I changed the plan and decided to use
the stranded wire and have the chamber brought to the surface.
I told McDonald to blow the ballast tank a little at a time, in
fact 3 seconds each time I gave the word. In the meanwhile, I
had about 10 men hauling on the wire by hand. The strand would
hold this amount of hauling. If we could pull the wire up until
the stranded portion was on deck, we could then get a secure hold
on the good part of the wire. At last we had the chamber light
enough to haul it in by hand and we hauled it to the surface where
the last of the survivors were rescued after a trying wait of
four and a half hours. All survivors were in excellent condition
and not even a cold developed from their exposure of nearly 40
hours.
The next diver to go down was Lt. J.K. Morrison. He took the descending
line aft to the after torpedo room hatch. This was a long hard
dive. Morrison did the job but the pressure nearly got him. Diving
on air to such depths is extremely hazardous because the compressed
nitrogen of the air acts more or less as an anesthetic. Only the
greatest will power and determination will see the diver through.
Diver Baker then went down and attached the haul down wire to
the after hatch. Strange to say, he too lost the wire once before
he made it fast.
Badders and Mihalowski then went down in the rescue chamber to
see if there was anyone alive in the after end of the submarine.
This brought back the sad but not surprising word that all was
flooded and no signs of life. Thus the rescue operations were
competed, with 33 lives saved and 26 lost.
On the 25th orders were received from the Navy Department to salvage
the wreck.
After one or two exploratory dives it was clearly indicated that
we had little chance of success unless we used helium.
At the Experimental Diving Unit we had found that the ill effects
of nitrogen under high pressure were almost entirely eliminated
when using helium oxygen mixture as a substitute. We had spent
nearly two years developing the proper decompression procedure
following exposures with helium. Unfortunately some writers had
created the impression that very little, if any, decompression
is required when using helium. I have found in experimental work
that most failures are caused by disregarding the simple laws
of physics. Here was an example. Helium, nitrogen, argon or any
other non-reacting gas that might be used as a dilutent or carrier
in respiration, goes into the blood in simple solution by way
of the lungs. As pressure is applied this gas is distributed throughout
the body and enters the various tissues, water, fat etc. The quantity
of gas that enters depends on the rate of blood supply. The tissues
with great blood supply such as the brain, kidney, liver, stomach
are fast tissues while those with a meager supply such as fat,
joints, bones, etc. are called slow tissues. Naturally given time
enough all tissues approach a condition of full saturation for
the given pressure. It follows that when the pressure is released
the non-reacting gas must be given an opportunity to come off
and if insufficient time is taken, those parts known as slow tissues
will be the first to give trouble by the gas forming as bubbles.
While gas does move from one part of the body to another by direct
diffusion as well as by the blood stream, and the rate of diffusion
varies with various gasses, it can be clearly seen that all gasses
must require decompression.
The theory of handling helium had been worked out, but the equipment
for handling it was not quite ready when we were called to this
job. That is the reason that helium was not used immediately.
However, we started in, within a few days, to use the helium and
thence forth used it exclusively when working at great depths.
Knowing that 2.5 atmospheres of oxygen is safe to breath, the
percentage of oxygen in the helium mixtures was calculated to
give slightly less than this amount, and was roughly 28%. Since
the gas that goes into solution in the blood varies directly as
the percentage present in the lungs, it is advantageous to use
as low a percentage of helium and as high a percentage of oxygen
as is possible, but keeping the oxygen tension below 2.5 atmospheres.
In order to conserve helium which costs the government about one
cent per cubic foot we devised a means of recirculating the gas
in the helmet, through a CO2 absorbent, using a small gas supply
as the driving agent, by admitting it through a venturi tube.
By this means the oxygen supply was adequate in the driving gas
and CO2 was kept at its proper level. This apparatus was not quite
satisfactory at first but by making daily corrections and with
the assistance of Mr. Philip Drinker and his friends we finally
obtained satisfactory performance, and used the helium.
The minds of the divers were clear and they were so much more
efficient when breathing helium that all divers were quickly converted
to helium users by choice. As regards to this mental effect I
feel sure that there is a definite relation between the molecular
weight of the carrier gas to the mental effect. For instance the
ratio of molecular weights of helium to nitrogen is as 4 is to
28, and the consensus of opinion of the divers as to feeling of
depth seems to verify this. As a further study of the effect we
used argon, molecular weight 40 as a carrier gas and found the
effects on the minds to be similar to nitrogen, but proportionally
worse. At ten atmospheres, I myself, was able to endure breathing
a mixture of argon and oxygen, but a few moments. At atmospheric
pressure the argon was not unlike air. If hydrogen were not so
dangerous as an explosive it might make the ideal carrier gas.
It may be used in the future for very great depths where the percentage
of oxygen required would be very low.
The greatest single development produced on this job was the decompression
system. Divers were brought by stages, calculated to be safe,
to 50 feet. From this depth they were brought quickly to the surface,
undressed and placed in a pressure tank within five minutes after
surfacing. There he was fitted with a mask and given pure oxygen
for a time sufficient to remove all of the excess gas from his
body. 50 feet of salt water is equivalent to 1-1/2 atmospheres
of pressure which added to the atmospheric pressure gives us 2-1/2
absolute. At this pressure the blood stream can handle in physical
solution just about the amount of oxygen that is required by the
body. Thus the blood stream as transportation is free to carry
the greatest amount of the helium away to the lungs. Since the
solubility of a gas in a liquid varies as the pressure, at a pressure
of less than 2-1/2 atmospheres, the carrying capacity of the blood
would be reduced, hence it would take longer to remove the gas.
Since at pressures substantially greater than 2-1/2 atmospheres
man develops serious symptoms, commonly and I believe erroneously,
called oxygen poisoning, we do not desire to use higher pressures.
It is my own opinion that when the oxygen tension is increased
beyond 2-1/2 atmospheres, the carbon dioxide removal is interferred
with, for the reason that the oxygen in the hemoglobin is not
reduced and the hemoglobin is unable to function as a chemical
carrier of carbon dioxide. The removal of carbon dioxide by physical
solution alone is insufficient. If this theory were correct we
would expect to find the venous blood stream so crowded with CO2
in physical solution that the removal of helium or other carrier
gases would be interferred with. This is, in fact, exactly what
we did find. The amount of helium or nitrogen given off when breathing
oxygen, following a measured exposure, reached a maximum at 2.5
atmospheres and then fell off rapidly as the oxygen tension was
increased. The symptoms developed by breathing excess oxygen were
found by Dr. R.A. Behnke to disappear very rapidly when the pressure
was released and to leave no after effects. This gives further
evidence that the symptoms are caused by excess carbon dioxide
and not a "poison." Were were little concerned over
the possibility of our divers developing symptons from breathing
excess oxygen.
An interesting problem arose when using helium which was easily
explained once we saw the light. Divers suffered much more from
cold water, than from breathing air. The answer was that the specific
heat of helium is greater than nitrogen and body heat was lost
through radiation from the body. The development of electrically
heated clothing solved this one. Resistance wire, wrapped in glass
thread woven into glass cloth to reduce the fire hazard, was made
up into panels. These were inserted between layers of wool. Electricity
supplied by storage batteries furnished as much heat as was necessary.
Should the wreck of the Squalus have been brought from
240 feet to the surface rapidly, the change in pressure would
have been about 107 pounds per square inch. Compartment hatches,
ventilation valves and tanks cannot withstand such pressures inside.
Consequently it was impossible to raise the hull in a single lift.
In order to control the lift it was necessary to attach pontoons
at each end of the hull, with wires or chains long enough so that
short controlled lifts could be made. For instance the first lift
of 80 feet was made by setting pontoons 80 feet from the surface
and using them to check the rise of the hull above that point.
Then when she hung on the pontoons 80 feet off the bottom we towed
her into shallower water. That is in general how the lifts were
made.
Permanent pad eyes or chains are not carried on submarines for
sound technical reasons. It was, therefore, necessary to get wires
and then chains under the hull at each end. Forward this was easy
for the bow was up high enough to allow us to drag a wire under.
But aft it was different. The stern was buried 18 feet into hard
blue clay. To have tunneled under by usual methods at that depth
was unthinkable.
We developed a tunneling lance. It was made up of 7 sections of
pipe tapered from 1-1/4" diameter up to 2-1/2". Assembled,
the whole lance was curved to the shape of the hull at the point
at which we desired to go under. This point was at the shafts
and we desired the chanins to be placed between the hull and the
propeller shafts so that they would be held from slipping forward
or aft by the propeller struts. On the entering end of the smallest
section of pipe, a minature nozzle was attached. This nozzle had
an opening for a stream of water on the forward end and anumber
of smaller holes leading aft at an angle for water to flow back,
thus to counter balance the forces of water, a hose was attached
to the trainling end of the section of pipe. This was lowered
down to a diver and he pointed it over the side. We turned on
the water and the pressure tunneled a hole next to the hull down
toward the keel. As each section disappeared over the side the
hose was disconnected and a new section of pipe lowered to the
divers to be attached to the end sticking out of the mud. When
it was estimated that enough of the lance was under the hull,
the water was turned off and air pressure was turned on. On the
oposite side of the deck, in almost exactly the desired position,
the bubbles were seen to be coming up. A wire snake was then run
through the lance and the end was recovered on the other side.
This was done on the 21st of June, 27 days after work began. At
the end of 50 days work, connecting hoses, rigging pontoons, attaching
bow and stern towing cables, the first lift was attempted. We
raised the stern successfully then the bow. The bow came up like
a mad tornado, out of control. Pontoons were smashed, hoses, cut
and I might add, hearts were broken. It was the 13th of the month,
July. Exactly 20 days of mopping up was required before we could
again rig for another try. The second try was successful.
The hull was raised about 70 feet from the bottom and towed into
shallower water on 12 August. We all felt very much encouraged
because it was the end of our very deep diving and we knew that
the system would work. 248 dives were made to the bottom without
a serious casualty. But two cases of bends were developed and
both of these could definitely be traced to the divers' coming
up too rapidly. One of the cases would have been serious but for
the prompt and correct treatment administered by Dr. O.D. Yarbrough.
Squire, who had been trying to dig a hole in the mud with a tunneling
hose, overworked, lost consciousness and blew up. His suit inflated
and he came all the way to the surface. Quick and efficient handling
by the dressing crew soon had him on board where his helmet, belt
and shoes were removed and he was carried into the recompression
chamber, still unconscious. The pressure was put on and built
up rapidly to 200 pounds before Squire showed signs of recovery.
When he did recover consciousness he was in great pain and raved
and threshed [thrashed] about like a wild man. After about half
an hour at that pressure he became normal and the long process
of treatment begun. He was kept in the chamber for 16 hours and
when he finally emerged the following morning he was little sore
but otherwise fully recovered.
The other case was that of Crosby. After a routine dive Crosby
came to his first stop at 90 feet. In order to help the tenders
he lightened his weight by inflating his suit, good procedure
when breathing air but dangerous when using helium, because of
the rapid diffusion of the gas into the blood stream keeps it
super-saturated and too rapid ascent might start bubbles in the
blood vessels. Crosby complained of pains in his stomach at the
90 foot level. Lt. Wheland, one of my assistants, was supervising
the dive and watched Crosby closely. He appeared to recover and
was given normal decompression. Later in the evening Crosby developed
symptoms of a serious nature. He was returned to the chamber and
given treatment. He responded to the treatment and recovered completely.
These were the only cases of the bends in the entire job with
a total of 628 dives. This is a record of which we are very proud.
Source: Biographical files, Operational Archives, Naval
Historical Center.