218 THE SUBMARINE OF TO-DAY AND TO-MORROW. 



We have made one contribution, possibly, in this country, towards the navigation of the 

 submarine. You understand that when an electric cable has direct current flowing through it 

 the cable itself becomes tremendously magnetic. At Niagara Falls not long ago they had an 

 experience showing how magnetic a harmless copper cable may become. There was a tunnel 

 containing cables on either side, which conveyed current to Buffalo. On the Buffalo lines one 

 sleety night they had a short circuit, and the onrush of current through the cables was such 

 that it ripped the cables from their moorings, some 12 feet apart, and in their tremendous rush 

 together they killed a man who happened to be going through the tunnel at the time. That 

 was simply by virtue of the magnet lines of force about a cable. 



In direct current — and all storage batteries must have direct current — there is a mag- 

 netic circulation about every cable that is constantly in one direction, and will easily turn a 

 magnetic needle "in a ten-acre lot," the magnetic needle in a compass. When you have a 

 compass in the small confines of a submarine, you cannot get it in a ten-acre lot. As soon as 

 you put 3,000 or 4,000 amperes through any of the cables, the needles in the compass go 

 around, and it never goes clear back and the directional function is lost. Another system of 

 guiding the submarine has been sought and found, and now we have gyro-compasses, which 

 are manufactured here in New York, on the submarines of nearly every navy in the world, 

 and they are found to be reliable and useful. Some tests were made not long ago with that 

 compass on the submarines that went in through the Dardanelles, under the mine fields, and 

 into the Sea of Marmora, and one of them remained there four weeks, had the compass 

 running every second of the time, and was able to get only two sun readings in that four 

 weeks. The commander reports that each time when he could take an observation he found 

 himself exactly on the scratch line. It is a comfortable feeling for those in a submarine to 

 know that they have a compass upon which they can rely. 



The compasses were installed on these submarines that went to join the Russian fleet and 

 made a journey of 1,600 miles, in which many difficulties of navigation were encountered, 

 and the compasses were found to be reliable and very accurate. Some of these officers have 

 received Victoria Crosses, and a number of letters have been received expressing very cordial 

 appreciation of the gyro-compass and satisfaction that they were able to navigate the sub- 

 marines so satisfactorily. 



The gyro-compass makes it possible to do another thing which is very valuable in con- 

 nection with the torpedo fire from a submarine. That is, we put a repeater compass — you 

 understand the master compass is usually not used directly — we have repeaters which are 

 coupled with the master, the accuracy of which, in following the compass, is 1/12 of a 

 degree, a time lag of .001 of a second. We hang one of these around the skipper's neck, and 

 he has a little repeater right before him with a 26-foot flexible cable on it, permitting him to 

 go into the prow of the submarine and stand with his thumb on the air discharge valve of the 

 torpedo tube, so that after he has been up and taken a last bearing of the target with the 

 periscope and knows that he is within the yawing angle, then when the submarine gets 

 exactly to say 71^4 degrees he is enabled to instantly discharge his torpedo and gets practi- 

 cally 100 per cent hits. If he has a torpedo in the tube, it will go straight, because the aim of 

 that torpedo is due to the aim of the submarine and this is dead accurate. We feel we are 

 well along with one problem — a serious one, too — and that is this aid to navigation. 



We believe that the same progress is going to be made in reference to the engine. This 

 paper states that the present Diesel engines require between 50 and 60 to 100 pounds per 

 horse-power. That is a serious objection to the Diesel engine, and it is felt that some 

 improvement should be made in this line. 



