Engineering Wonders of the World
Volume I

Forfatter: Archibald Williams

År: 1945

Serie: Engineering Wonders of the World

Forlag: Thomas Nelson and Sons

Sted: London, Edinburgh, Dublin and New York

Sider: 456

UDK: 600 eng - gl.

Volume I with 520 Illustrations, Maps and Diagrams

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SUBMARINE BOATS. 431 ately the depth, amount of ballast, gasolene, and air pressure, “ trim ” and “ stability ” of the boat, at any particular moment. The captain, who works the vessel when under way, has every device under complete control from his small platform beneath the conning tower. In the interior are bells, speaking-tubes, and, in the latest craft, telephones for communication between the navigator and the various parts of the boat. There are two compasses for navigating purposes, one located outside the hull, but observable from the interior of the conning tower, and the other in the conning tower itself. The armament consists of a single torpedo tube situated in the bows or forward part of the boat, its opening end 2 feet below the Armament. water-line when the boat is light. The tube is closed by a hinged flap, lifting upwards and operated by an air-cylinder, or by hand, at will, from the interior of the boat. This concludes the description of a sub- marine of the early Holland type, from which have developed all the subsequent submersible craft of the American and British Navies. Whilst we, however, have followed these particular lines, other nations have experi- mented for themselves, and the designs of ships accepted in their submarine fleets differ entirely and in almost every external par- ticular from that described above. Inter- nally they have most features in common, What every constructor is aiming at is a vessel able to navigate on the surface like an ordinary ship, and to move beneath the sur- face of the sea in a direct line for the object it is desired to reach, while retaining stability in every sense, and remaining at all times under the absolute control of its commander. Moreover, it must possess the maximum of speed, safety, offensive power, and habitabil- ity, a trustworthy means of propulsion, and complete independence of all exterior help while in action. To submerge submarines from the surface condition three systems have been tried — those of (1) vertical propellers ; (2) rudders inducing a descent c ^}eans <>1 . , ° , Submersion. on an even keel ; (3) stern rudders sending the boat down at an angle, nose first. Vertical propellers, so placed that when revolved they draw or drive the hull beneath the surface, and, on being reversed, bring it to the top again, have been tested many times, without success, so the system may be dismissed as impracticable. The second means of submersion—on an “ even keel ”—has many advocates. Here the horizontal rudders or diving-planes are so arranged that their action draws the ship under water without affecting her longi- tudinal trim. Many modern submarines dive in this manner. The system adopted for British and United States submarines of div- ing “ by the head ” makes use of horizontal rudders in the stern. These, affected by the water pressure set up by the ship’s move- ment, dip the “ nose ” down and the “ tail ” up, causing a dive. The angle of descent is not steep, and the action of the rudders can be controlled to a nicety. The means of watching from beneath the surface what is happening above are very limited, though improvements in the instru- ments employed are being made constantly. The “ optical tube ” (otherwise known as peri- scope, hyposcope, or cleptoscope) is based on the principle of reflecting mirrors placed parallel to one another at opposite ends of a long tube. Images of objects outside the boat and above the surface of the sea are cast on to the upper prism and reflected down to a mirror of para- bolic section, which corrects distortion of image. The picture given is exceedingly small, and must be magnified. Were it not for the recent great improvements in the instruments used, particularly by the British Navy, their value would be slight indeed. Many French “ submersibles,” as distin-