698 



jy 



Popular Science Monthly 



Insulating a 



Gulls, which have been fed from a submarine, get the 

 habit of watching for the underwater craft, and thus 

 reveal their presence to the watchful eye of the enemy 



Training Sea-Gulls to Become 

 "Spotters" of Submarines 



NAVAL officers have frequently had the 

 opportunity to observe that swarms 

 of sea-gulls follow in the wake of sub- 

 marines. The birds are attracted by the 

 unusual spectacle of a whalelike monster 

 moving through the water, and are eager 

 to pick up garbage. 



This observation which, in a few in- 

 stances during the present war, is said to 

 have led to the timely discovery of the 

 dreaded proximity of a U-boat, suggested 

 to Dr. A. D. Pentz, Jr., of New Brighton, 

 N. Y., the plan of training the gulls to 

 follow in flocks in the wake of subma- 

 rines. He suggests the use of a hopper, 

 fifty-four inches long, made of sheet steel. 

 It is securely bolted to the top of a 

 submarine and filled with chopped 

 fish. This bait is released from time 

 to time by the turning of a crank 

 operated from the inside of the sub- 

 marine used for training the gulls. 

 The bait, which would naturally 

 rise to the surface of the water, 

 would attract the gulls and cause 

 them to follow the submarine. 



Hot Rifle 

 for Bayonet Use 



APPRECIATING the fact 

 £\. that a rifle barrel, heated 

 with much rapid fire, is not a 

 particularly inviting article 

 to handle, and that neverthe- 

 less it must be handled when 

 it is required to use the 

 bayonet, Mr. Henry Brewer, 

 of Connecticut, has invented 

 an insulating device. 



The insulator consists of a 

 perforated metal shield, a 

 little more than semi-circular 

 in cross-section, and suffi- 

 ciently larger in diameter 

 than the barrel to form an 

 insulating space. It is not at 

 all in the way of the user 

 of the rifle, and as it is 

 merely attached with two or 

 three screws, it does not in- 

 terfere with the proper clean- 

 ing and care of the rifle. 

 The inventor asserts that in 

 view of the perforations in 

 the plate it will give a much better grip 

 than it was possible to obtain before, as 

 manifestly the hand will not slip on 

 the rough plate the way it would 

 on the smooth, hot, rifle barrel. 



This insulating 

 shield will enable a 

 man to grasp a hot 

 rifle barrel without 

 discomfort or slip- 

 ping when he makes 

 use of his bayonet 



Bavonet-mountvi™, 



m 



Clamping screws- 



Ventilating 

 openings 



