168
The Last Resource
he quickly became accustomed to the German spoken by Dr Horst
Hartmann during a dry dive to a simulated depth of 800 feet. The
Conshelf divers, themselves, claimed that after a few days they could
understand each other’s oxyhelium voices. Certainly, it seems
possible to reduce the confusion of the strange sound by more
controlled breathing and slower speech. Nevertheless, considerable
effort is going into developing unscrambling devices to improve
communication both between divers and between them and people
on the surface. It has even been suggested that some kind of articial
larynx—voice box—might be used. Diving has always been
hindered by difculties in communication but, if life and work
underwater is to be bearable let alone manageable, some kind of
solution other than the hand signals and tugs on lines used in shallow
dives must be implemented.
To help overcome the problem of heat loss, divers are almost
‘cooked’ within the underwater habitat. Outside in the water it is
quite another matter—you cannot heat up the entire ocean.
Electricity and hot—water circulation have been used to heat the
diving suits. The Cac/mici system used hot water, for example, and
the Sealab 2 divers experimented with electrically heated suits.
Radio—isotopes, such as plutonium—238, offer a further alternative
source
of energy for a compact heating unit. The problem is
aggravated by the loss of insulation suffered by contemporary
diving suits at depths much below 200 feet. Above this depth the
porous
structure of the foam material traps air to form a spongy
insulator, but below zoo feet the pressure of the water soon presses
the suit at. One solution used by Conshelf3 divers was to wear a
vest made of an incompressible material incorporating thousands
of glass ‘micro-balloons’ lled with carbon dioxide to provide the
insulation. At that time the material could not be used to protect the
whole body beneath the diving suit because the material was
suiciently rigid to interfere with the diver’s freedom of movement.
But even the best insulation will be insuicient protection for long
stays in the cold deep water and the diver will need some form of
auxiliary heating if he is to work efciently.
Breathing gas mixtures poses many problems other than those
created directly by the use of helium. Supplies of gases are limited
and, to remain operational, fresh stocks must be sent from the
surface or the original supply must be conserved until the end of
the stay by ‘scrubbing’ the gas clean of impurities and re—using it:.
The Last Resource
he quickly became accustomed to the German spoken by Dr Horst
Hartmann during a dry dive to a simulated depth of 800 feet. The
Conshelf divers, themselves, claimed that after a few days they could
understand each other’s oxyhelium voices. Certainly, it seems
possible to reduce the confusion of the strange sound by more
controlled breathing and slower speech. Nevertheless, considerable
effort is going into developing unscrambling devices to improve
communication both between divers and between them and people
on the surface. It has even been suggested that some kind of articial
larynx—voice box—might be used. Diving has always been
hindered by difculties in communication but, if life and work
underwater is to be bearable let alone manageable, some kind of
solution other than the hand signals and tugs on lines used in shallow
dives must be implemented.
To help overcome the problem of heat loss, divers are almost
‘cooked’ within the underwater habitat. Outside in the water it is
quite another matter—you cannot heat up the entire ocean.
Electricity and hot—water circulation have been used to heat the
diving suits. The Cac/mici system used hot water, for example, and
the Sealab 2 divers experimented with electrically heated suits.
Radio—isotopes, such as plutonium—238, offer a further alternative
source
of energy for a compact heating unit. The problem is
aggravated by the loss of insulation suffered by contemporary
diving suits at depths much below 200 feet. Above this depth the
porous
structure of the foam material traps air to form a spongy
insulator, but below zoo feet the pressure of the water soon presses
the suit at. One solution used by Conshelf3 divers was to wear a
vest made of an incompressible material incorporating thousands
of glass ‘micro-balloons’ lled with carbon dioxide to provide the
insulation. At that time the material could not be used to protect the
whole body beneath the diving suit because the material was
suiciently rigid to interfere with the diver’s freedom of movement.
But even the best insulation will be insuicient protection for long
stays in the cold deep water and the diver will need some form of
auxiliary heating if he is to work efciently.
Breathing gas mixtures poses many problems other than those
created directly by the use of helium. Supplies of gases are limited
and, to remain operational, fresh stocks must be sent from the
surface or the original supply must be conserved until the end of
the stay by ‘scrubbing’ the gas clean of impurities and re—using it:.