Scientists used to explore on the surface of the ocean.（46). They want to know about the o

Scientists used to explore on the surface of the ocean.(46). They want to know about the ocean water and the plant and animal life deep in the ocean.

In 1934, the scientist William Beebe dived 3,000 feet below the surface in a hollow steel ball. In 1935, Auguste Piccard dived 10,330 feet. In 1960, his son Jean dived to a depth of 35,800 feet.

All these early dives were deep. (47). They had to come back up to the surface after a few seconds. Scientists needed to stay down longer to study life below the surface. Gradually, they succeeded. Cousteau, a Frenchman, was able to keep men down to a depth of 36 feet for one month and to a depth of 90 feet for a week.

(48). With this new equipment, men can stay below the surface for days or even weeks. In 1962, Cousteau set up a research station 35 feet below the surface. Then in 1964, he set up another station on the ocean floor of the Red Sea.(49).

Many countries are now studying undersea living.(50). The United States has a laboratory 50 feet down on the ocean floor off the Virgin Islands. In 1970, five men lived there for two weeks. Then a team of five women scientists stayed in the laboratory. Next came other teams of men. All were there to explore the ocean depths and to make plans for the use of its resources.

(46)

A. This was the first undersea station to operate without help from the surface.

B. But the divers could not stay down for very long.

C. Scientists hope to find enough mineral, vegetable, and animal wealth there.

D. Now they are exploring below the surface, too.

E. The Soviet Union has an undersea laboratory in the Crimean Sea.

F. Now scientists are developing even better equipment.

(47)

A. This was the first undersea station to operate without help from the surface. B. But the divers could not stay down for very long. C. Scientists hope to find enough mineral, vegetable, and animal wealth there. D. Now they are exploring below the surface, too. E. The Soviet Union has an undersea laboratory in the Crimean Sea. F. Now scientists are developing even better equipment.

(48)

A. This was the first undersea station to operate without help from the surface. B. But the divers could not stay down for very long. C. Scientists hope to find enough mineral, vegetable, and animal wealth there. D. Now they are exploring below the surface, too. E. The Soviet Union has an undersea laboratory in the Crimean Sea. F. Now scientists are developing even better equipment.

(49)

A. This was the first undersea station to operate without help from the surface. B. But the divers could not stay down for very long. C. Scientists hope to find enough mineral, vegetable, and animal wealth there. D. Now they are exploring below the surface, too. E. The Soviet Union has an undersea laboratory in the Crimean Sea. F. Now scientists are developing even better equipment.

(50)

A. This was the first undersea station to operate without help from the surface. B. But the divers could not stay down for very long. C. Scientists hope to find enough mineral, vegetable, and animal wealth there. D. Now they are exploring below the surface, too. E. The Soviet Union has an undersea laboratory in the Crimean Sea. F. Now scientists are developing even better equipment.

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