NEW CONCEPTIONS IN SCIENCE 



Two tuning-forks which have the same width 

 of vibration amplitude is a better word will set 

 each other going if one be silent. They will have 

 no effect on a fork of differing amplitude. 



As with the sound-waves, so with the electric. 

 A sender and a receiver must be "tuned," so to 

 speak, or within certain limits one will not act 

 on the other. This is what is called syntony. 

 It is towards narrowing these limits of sympathy 

 that all the workers in this field are now striving. 

 Signor Marconi feels that the problem is largely 

 solved. It is easy to see that this would settle 

 two points at once first, preventing any mix-up 

 in messages; second, insuring a large measure of 

 secrecy. 



In order to "steal" a message, it would be 

 necessary to know the rate of vibration of the 

 sender, and at the same time possess an instru- 

 ment which could be syntonized to respond. 



That this difference of vibration is effective has 

 been demonstrated in another field by Professor 

 Mercadier's researches. Over an ordinary wire it 

 is now possible to send four messages each way 

 at the same time. Mercadier, employing Hertz 

 waves, sends eight wave messages each way simul- 

 taneously with the others, and without the other 

 operators being aware of what is going on. That 

 is twenty-four superimposed sets of disturbances in 



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