Page 60 - Wonderful Creatures: Children! Have You Ever Thought ?
P. 60
WONDERFUL CREATURES
AN INTERESTING
CREATURE: THE NAUTILUS
You must have seen submarines on TV or in journals. These ves-
sels, which are capable of operating far below the surface of the sea
without being noticed, are used in ensuring national security and in
some scientific research. How submarines operate is: As the spe-
cial diving tanks in a submarine are filled with water, the vessel
becomes heavier than water and sinks deep down in the ocean. If
water in the tank is emptied and replaced by pressurized air, the
submarine rises to the surface of the water again.
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