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Deep-Sea Machines
by Jennifer Uscher
Bathysphere
The bathysphere—bathys is Greek for "deep"—was developed in the early
1930s by William Beebe and Otis Barton, two explorers from the New York
Zoological Society. It was a 4,500-pound hollow steel ball about five
feet in diameter,which was raised and lowered from a ship by a cable.
Electrical connections powered its oxygen system and searchlight. Air came from
oxygen tanks fitted to the interior, with trays of powdered chemicals to absorb
moisture and carbon dioxide. The oxygen was kept circulating by hand-held woven
palm-frond fans. In 1934, Beebe and Barton dropped 3,028 feet down into the
ocean off the coast of Bermuda, relaying news of their finds by telephone cable
to a ship on the surface. They recorded every animal that passed before their
portholes, including fish and invertebrates never before seen. Because of the
attached steel cable and winch, the bathysphere wasn't very maneuverable; it
could only go straight down and straight back up again.
Bathyscaph
The bathyscaph, designed by Belgian scientist Auguste Piccard (1884-1962), was
not suspended from a surface vessel but rather attached to a free-floating
tank. (The tank was filled with petroleum liquid, which is lighter than water
and hence buoyant.) Piccard's first bathyscaph, the FNRS-2, was referred to as
the "submarine balloon" because its heavy-metal ballast, attached by
electromagnets, allowed it to sink to a desired depth when engaged and rise to
the surface when released. It had greater maneuverability than the bathysphere,
though it did not fare well in tests. Piccard and his son Jacques later
designed and built a new bathyscaph, the Trieste. In 1953, they descended in it
to a depth of 10,330 feet in the Mediterranean. The Piccards sold the Trieste
to the U.S. Navy in 1958. On January 23, 1960, the Trieste set a new world
record of 35,800 feet when it touched bottom in the Marianas Trench near Guam.
When the American submarine Thresher sank off the coast of New England in 1963,
the Trieste was used to find and photograph the remains at the bottom of the
sea.
Alvin
The Alvin submersible is operated by the Woods Hole Oceanographic Institution
on Cape Cod, Massachusetts. Considered the world's most productive submersible,
it routinely makes more than 150 dives a year. It has been re-built numerous
times since it was first designed in 1964. The original aluminum frame has been
replaced by titanium, and the depth range has been increased from 13,124 feet
to 14,764 feet. In 1966, Alvin, together with a Navy robot, retrieved a
hydrogen bomb lost in the Mediterranean after the collision of an American B-52
and a refueling tanker. During preparations for a dive off Cape Cod in 1968,
the steel cables used to raise and lower Alvin into the water snapped, sending
it 5,065 feet to the seafloor (fortunately with no one on board). When it was
retrieved 11 months later, scientists were stunned to find that the bologna
sandwich contained in a plastic box in the sunken submersible was still edible.
Continue: Johnson Sea Link
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