Masterpieces of Science 



son and Mr. John Trotter have devised means for 

 the direction of torpedoes by ether waves, such 

 as those set at work in the wireless telegraph. 

 Two rods projecting above the surface of the 

 water receive the waves, and are in circuit with a 

 coherer and a relay. At the will of the distant 

 operator a hollow wire coil bearing a current draws 

 in an iron core either to the right or to the left, 

 moving the helm accordingly. 



As the news of the success of the Marconi tele- 

 graph made its way to the London Stock Ex- 

 change there was a fall in the shares of cable 

 companies. The fear of rivalry from the new 

 invention was baseless. As but fifteen words 

 a minute are transmissible by the Marconi sys- 

 tem, it evidently does not compete with a cable, 

 such as that between France and England, which 

 can transmit 2,500 words a minute without diffi- 

 culty. The Marconi telegraph comes less as a 

 competitor to old systems than as a mode of 

 communication which creates a field of its own. 

 We have seen what it may accomplish in war, 

 far outdoing any feat possible to other appa- 

 ratus, acoustic, luminous, or electrical. In quite 

 as striking fashion does it break new ground in 

 the service of commerce and trade. It enables 

 lighthouses continually to spell their names, so 

 that receivers aboard ship may give the steers- 

 men their bearings even in storm and fog. In 

 the crowded condition of the steamship "lanes" 

 ' which cross the Atlantic, a priceless security 

 against collision is afforded the man at the helm, 

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