Bisbee daily review., 1921-03-13
lLUND REVIEWS WORK OF EDISON DURING WAR TO HELP UNCLE SAM
 EOUTWIT THE GERMAN SUBMARINES

Inventions of Thomas A. Edison During the War" was the subject of paper presented at the last meet ing of the Bisbee Chapter of the American Association of Engineers, by H. A. Lund.
 In January, 1917, Thomas Edison was asked by Secretary Daniels to come to the aid of the country by de- voting himself to the study and sug- gestion of such ideas and inventions as he might deem useful if the Uni ted States should become involved in the war with the central powers.
 Edison, accordingly, put his busi- ness affairs entirely in charge of his officials gave up his other experiment tai work and investigations, and de- voted himself exclusively to this work of the government, and remained so engaged for about two years
 List Of Devices Worked On
 The following list includes the most important devices worked on by Edison while helping Uncle Sam to outwit the German submersibles:
 Detecting submarine by sound from moving vessel: With the device per fected there was no difficulty in hear 1 ing a torpedo more than 4O00 yards away, which is far beyond the effect | i've distance from which a torpedo
 may be launched from a submarine. Quick turning of ships: This was effected by means of sea-anchors. In test a loaded vessel 325 feet in length was turned 90 degrees from her course in two minutes and ten seconds, with an advance of only 200 | feet, by the use of four sea-anchors | Collison mats: One of the schemes suggested by Edison to minimize the loss of torpedoed vessels covered the launching of collision mats. These mats were arranged so that they could be launched in a few seconds, to cover the hole made by the explosion of a torpedo.
 Camouflaging ships and burning an- thracite: Edison's scheme is des- cribed in a report forwarded by him to Washington, and which reads as follows in part:
 Burn sAntharcite In Danger Zone . T have advised the Cunard com
 pany to carry 200 tons of anthracite coal, and to burn this only in the danger zone. This amount of yoal will carry the vessel in and out of the danger zone, and the only extra eX- | pense for this is S275. I have also had the engineers of the New York Edison company teach the engineers of the Cunard line how to effectively burn anthracite coal so that there will be no loss of speed with any cargo boat, which type of boat is the Cnly one that I am working on By suppression of smoke, ana by camouflage Edison cut the distance of visibility from 20 miles down to IS miles.
 Obstructing torpedoes with mats:
 Edison proposed the use of a simple gun similar to trench mortar, from which could be fired an obstruction netting.
 Underwater searchlight: One of the problems placed before Edison was to provide a searchlight to be used un- der water by submersibles. Oleum cloud shells: The experiment with shells containing oleum which on
 bursting would form a dense white suffocating cloud, were followed by Bdison for several months. He was greatly impressed with the desirabil- l ity of this type of shell for many
 
 cloud to blind the vision of enemy ships.
 Signal 40 Words Minute High-speed signalling searchlights:
 Edison devised one with which Morse signals could be flashed at the rate of 40 words minute.
 Water penetrating projectile: Dur ! ing the height of enemy submarine activity Edison devised type of pro- | jectile that would enter the water direct, without ricochet, and which
 would continue it's course without de- | Election and make penertative hit. ZigZagging ships: Edison pointed out to navy officials that it was use
 less for ships moving less than 10 ! knots an hour to zigZag and that the results only led to a Joss of total
 carrying capacity. French naval of ficers subsequently, arrived at the
 same conclusion.
 i Obtaining nitrogen from the air; He developed an effective process. | Device for lookout men: A simple
 device perfected by Edison for use by
 lookout men in watching for peris-
 copes in bright sunlight. By the use of this device in the full light of day | objects could be distinguished that
 were otherwise Invisible.
 Sound ranging: The determination
 of the location of hidden guns by ob-
 serving the time intervals between
 which the sound of their discharge reached several known points, was
 early taken up by. Edison. Actual tests
 made with modern guns, showed that
 under varying weather conditions the position of an unknown sound could be located within 2 percent, plus or minus, of the measured distance from the sound.
 Render Periscopes Useless
 Smudging periscopes: He perfected
 compound that would form film or
 the water in which submarines were
 operating, and would smudge the
 periscopes and thus render them use
 less for purposes of observation. This compound could not be removed iron
 the periscopes by the use of either 5 BELIEVES CARUSO WILL RETURN E