Underwater explosions are conducted to try measuring the thickness of the Earth's crust.
Round Lake, France.
Various shots of scientists studying underwater explosions - the explosions are conducted to help measuring the Earth's crust. Explosives going off in Round Lake. CU. Hand pressing button to let off explosive. Mass of water splashing high in the air as the explosion goes off. More shots of the scientists at work and the explosions - good shots of the explosions.
Date found in the old record - 09/10/1956.