Hiding a Ship in Smoke 



England equips her liners with an apparatus to produce 

 a smoke screen which hides them from submarines 



OCEAN liners flying the flag of England 

 are now being fitted with the smoke 

 ! screen apparatus invented by the 



'British Admiralty as a protection against 

 submarine attack. Several ships equipped 

 with the apparatus have already docked in 

 American ports. 



On each side of the afterbridge, where 

 there is always an officer on watch, two 

 funnel-shaped ventilators are placed, from 

 which dense clouds of chemical smoke 

 belch. The ventilators are rotated by a 

 ratchet mechanism which is controlled by 

 electric wires from the bridge of the ship. 

 The smoke, which is thick and heavy, is 

 forced out of the ventilators by a blower in 

 a long ribbon, from two to five miles in 

 length and a hundred feet high. 

 ' It is well-nigh impossible to drive or 

 force smoke or dense vapor against the 

 wind by mechanical means. Consequently, 

 the smoke screen is at the mercy of the 

 wind. The seven diagrams ac- 

 companying this article vividly 

 illustrate this. In No. i and No. 

 3 the smoke ribbon is shown 

 trailing straight away from 

 the ship, leaving both sides 

 and the bow of the vessel ex- 

 posed. In No. 4 

 the apparatus 

 gives but 

 scant pro- . . 

 tectlon, while 

 No. 5 shows 

 nearly one half 

 of one side 

 obscured. In 

 No. 7, which 



shows the wind and ship traveling in the 

 same direction, the screen is very effective, 

 enveloping the ship from bow to stern in a 

 thick pall of smoke. The method of smoke- 

 screening a line of battleships by torpedo 

 boat destroyers is shown in No. 6. Both 

 the battleships and the destroyers, travel- 

 ing at approximately thirty knots, maneu- 

 ver for a favorable wind direction before 

 the destroyers belch their smoke. With the 

 smoke screen or shield to cover them the 

 fleet conceal&its movements. Ordinarily the 

 number of destroyers varies with the number 

 of battleships, but not necessarily so. 



Although the captain on the bridge is 

 able to rotate the ventilators, he can not 

 throw a screen of smoke around his vessel 

 if the wind is against him. This is brought 

 out very clearly by diagram No. 2, which 

 shows how a submarine could choose 

 its own position and wait for its victim. 



DESTROYERS 



SMOKE SCREEN FOR BATTLESHIPS 



Two ventilators rotated by a ratchet device are placed one on each side of the afterbridge. 

 The smoke is either generated in the ship's fire box by burning oil or naphtha, or in a smudge pot 



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