130 DISCUSSION ON TWO PRECEDING PAPERS. 



If there is no further discussion, we will ask Mr. Millet to close the discussion on his 

 paper, and he will be followed by Commander Sawyer with his closing remarks. 



Mr. Millet: — I have very been much interested in what the speakers have had to say. 

 I want to say, gentlemen, in the beginning, that I am not a navigator or a scientist, but it was 

 my job — having spent several years in assisting to perfect this system — ^to go abroad and con- 

 vert the shipping companies and lighthouse authorities to the belief that they must abandon 

 the air and use the water. I think if I had gone to either of the gentlemen who have just 

 spoken and told them that was what I wanted them to do, they probably would not have re- 

 ceived me with open arms, and, in fact, nobody did. One reason why your captains did not 

 take any more interest in the matter was that it is not taught as an aid to navigation, and it 

 should be. It should be taught at Annapolis and should be in all your text-books ; it should 

 be just as much a matter of necessity for the captain, pilot or mate to know how to use this 

 apparatus as any other. If the commanding officers were given an opportunity to practise on 

 their own ships when there is no danger, so that they may know the sounds of their own ves- 

 sels, we would get ahead twice as fast as we have done. It would be the easiest thing for 

 Nature to put our ears on our shoulder-blades if she wanted to, but if she had done that we 

 would have heard our heart beat. One reason why the tanks are put so far forward is so 

 that they cannot hear all the movements of the machinery. In a general way the tanks are 

 placed there (indicating on blackboard). Let us suppose we have oscillators instead of car- 

 bon microphones. In the first place, the microphone, as you know from your telephone ex- 

 perience, hears everything that comes to it — scratch the holder with your finger, and you 

 get that sound. Ships' noises jar the microphone in just that way, and they contribute to 

 sending into your ears sounds you do not want to hear. I am not in the least interested finan- 

 cially in any system. I am simply anxious to contribute anything that comes from my ex- 

 perience extending over several years, anxious to contribute any knowledge I may possibly 

 have on this subject to the common experience. 



The only difficulty I have ever had in conducting tests for the British, French or Ger- 

 man navies was ships' noises at extreme distances — or people would talk in the room in which 

 the instrument was located, or hammer on the walls, or the pumps would start when they 

 ought not to, and these interfered with the proper hearing. I often wished there had been 

 some way of cutting out ships' noises, the rumbling of the screw, the vibration of the engines, 

 or what-not. The new invention called the oscillator does that. It is not only a good trans- 

 mitter of sound, but it is a better receiver of sound than the carbon transmitter is. Conse- 

 quently, you are not at all disturbed by anything which occurs on board the ship. 



Let us look into this thing further. You have two tanks like that (indicating on 

 blackboard) and get the direction all right. Suppose you put two more back here (indica- 

 ting). We know there is a certain zone of silence back here. With reference to these two 

 tanks, that is the zone of silence, because the sound cannot go from this side of the ship to 

 that tank. You will have another zone of silence there ( indicating on blackboard). If you 

 swing your ship for the benefit of the signaling apparatus, the same as you do for your com- 

 pass, you will know where the zones of silence are; and if you know those zones of silence 

 with reference to any bells that may be anywhere, that is all you want to know. If the bell 

 is over the stern, that is a good place to keep it. As I have said, I have no desire to advance 

 any particular system. I have no commercial interest in any, but what I want to do is to show 

 that these systems are practicable and efficient. It seems to me if this ship can send through 



