The Application of the Sixth Sense to Ships 



About one-half of mankind is able to hear the high note 

 given off by crickets, and the same is true of the voice of bats. 

 Extremely high notes have very little power ; they do not 

 travel far enough to be of any use at sea. 



In providing a ship with a sixth sense, we have to con- 

 sider three distinct devices : one for producing and sending 

 out the necessary waves, one for receiving the reflected 

 waves and making them audible by ringing bells, and 

 another apparatus for recording the amplitude of the waves. 



For producing the vibrations of waves, I prefer to use a 

 modified form of a siren, the disc being rotated at a suitable 

 speed by a motor of some kind, preferably an electric motor. 

 I prefer to use a very high pressure of steam, to have 

 all the parts large and strong, and to produce about fourteen 

 or fifteen vibrations per second. These will not come within 

 the range of the human ear, consequently they cannot be 

 considered as sound, and as they are of great amplitude and 

 power they are able to travel over great distances, and 

 when they come in contact with a body, the waves are 

 reflected back to the ship in the same manner. that sound 

 would be reflected back, but this echo would not be audible 

 to the human ear. I, therefore, provide an apparatus which 

 might be considered as an artificial ear. It is provided with 

 a large diaphragm tightly drawn over a drum-shaped cylinder, 

 and so arranged that the atmospheric pressure is always 

 the same on both sides, quite irrespective of any air blast. 

 It is, therefore, always able to vibrate freely in response to 

 the waves of the echo, and its vibrations are made to open 

 and close certain electrical circuits which ring a series of bells 

 of various sizes. If, for example, the object is very small 



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