The Birmingham age-herald., 1908-04-11

can head the bell, and that detracts from the efficacy of the system, for when captain thought he was in safe waters he came to disaster
 Now, my invention acts automatically and does away with the telephone re- ceiver altogether. When a ship comes within, say five miles of the sunken bell another bell on the ship Is set ringing automatically by the sound vibrations, and the captain is warned that he Is in a dangerous area. Do I make 1t clear?'
 'I think I understand, but l should like to know a little more about the trans mission of force. I mean what precise ly are these vibrations and how are they transmitted and received%'
 Well, we know that sound is vibration. If you strike bell with hammer you have vibration or resonance. In them selves these vibrations are small: they only affect the ear. In order to get what we call a mechanical effect all these lit tie vibrations must be added up until you get big one Once you get big vibration you can do anything. Take, for instance, a great log of wood, say two feet wide and 20 feet long. Place this log on two supports, and it Is we'll known scientific fact that you can break the log with your little finger By exer- cising pressure at the right time you can make the log vibrate, almost impercepti- bly at first, but gradually stronger and quicker, until all the little brations make one huge convulsion that shivers the log like a blow from an ax. That is precisely how sound vibrations may be made to work automatically.
 Can you explain how it is that the sound can be heard for a distance of five miles?'
 'I have told you that water is a splen- did conductor On the water you can hear the thud of passing steamer screw for miles, You will have read how the Indians detect the approach of an enemy by placing their ear to a surface of river. and how the divers for sponge signal to their comrades by striking two shells together. I am repeating this ele- mentary knowledge simply to show you how it is possible to make the water con vey sound vibrations so that they will cause bell to be rung or whistle to be blown
 s'It is more wonderful even than Mar conigram,'' I observed
 .srhe principle is really tie same, only the element is different. Submarine wire jess telegraphy is quite possible. By the way, here is a simple experiment in con oucting sound. Wood. you know, is a good conductor. Well, here is a piece of wood shaped like stethoscope Listen; you can hear the wind fairly distinctly. but place your ear to the wood, place tha orher end of the wood against the wall and note the difference"
 did as requested. and the roar of the wind was greatly intensified.
 With your system in perfect working crder, I should imagine that wrecks will. Le thing of the past" I observed.
 It will certainly make sea traveling much safer."
 There is another and a valuable point I suggested. Would it be possible by the ;id of your invention for the captain ot battleship to detect the presence of T submarine for a distance of several mi1es?' Mir. Gardner lit another cigarette and smiled enigmatically. q would rather you did not ask me anything bearing on the navy he said. T am in comniuni- cation with the authorities, and my lips are sealed''
 Although Mir. Gardner refused to an- c,yer my question, the reader will see for Himself, that if the system of automati.' signaling by sound is all that its dis soverer claims for it, the British navy will have tremendous advantage in war time. With the system installed on bat tie ships, submarines would cease to be the terror they now are. The appear ance of these silent. secret vessels would De signaled long before they could strike, and once put on the alert. the crew of t nattleship would know how to deal with fnc submerged enemy Mir Gardner ad- :tted that mines could be exploded and torpedoes directed by sound waves. therefore there is no reason why the ,Tasancn ct submarine could not be cornmunica led 10 battlcship It is satis factory to know. at any rate, that tho acga.ra..ty have ssie scheme undar cnn- sfderstian.
 1t must not be thought tha. Mr. Gsrl- Ter ;s n any sepsa q ''craHk."r He is an Inventor by profession and the products of his brain have found ready mar