1] Successful navigation beneath the surface of the water, though not carried to the extent imagined by Jules Verne, was a reality at the beginning of the twentieth century. Instead of twenty thousand leagues under the sea, less than a hundred leagues had been accomplished, but no one can foretell what the future may have in store. [2] The submarine is primarily utilized in wars. The weapon used by the submarine is the torpedo. The torpedo is itself a small submarine able to propel itself, and if started in the water toward a certain object, to go under water straight to the mark. It carries a heavy charge, either of guncotton or dynamite, which explodes when the torpedo strikes a solid object, such as a battle-ship.
[3] It would be very difficult for one submarine to fight another submarine, for the submarine when completely submerged is blind. It could not see in the water to find its enemy. The torpedo-boat-destroyer is able to destroy a submarine by torpedoes, shells full of high explosives, or quick-firing guns. Advantage must be taken of the moment when the submarine comes to the surface to get a view of her enemy.
[4] One of the great enemies of the submarine will probably be the air-ship, for while the submarine when under water cannot be seen from a ship on the surface, it can, under favorable conditions, be seen from a certain height in the air.
[5] The rising and sinking of the submarine depend on the principle of Archimedes. The upward push of the water is just equal to the weight of the water displaced. If the water displaced weighs more than the boat, then the upward push of the water is greater than the weight of the boat and the boat rises. However, the boat can be made to dive when its weight is just a little less than the weight of the water displaced. This is done by means of horizontal rudders which may be inclined so as to cause the boat to glide downward as its propeller drives it forward.

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How do the details in the 5th paragraph develop the claim in the text?