308 



Popular Science Monthly 



This modem subma- 

 rine has a disappear- 

 ing gun which folds 

 away below deck 



A Gun Which Will 

 Lie Down 



Pivot 



::::3i: 



THE submarine has — 

 been a defensive 

 weapon in most navies. 

 Apparently the Germans 

 were the first to realize 

 that it had offensive possibilities. We 

 found a patent the other day applied for 

 in the United States, by Julius Becker, an 

 employee of the Krupps. It proves our 

 point. 



It is interesting to note that the patent 

 was applied for in 1909, showing that 

 even then Germany was awake to the 

 uses of the submarine as an offensive 

 weapon. 



A hollowed-out compartment on the 

 deck of the boat receives the gun. The 

 gun barrel is mounted on a pivot fork, 

 turned toward the muzzle, so that when 

 not in use, the gun can be folded down 

 horizontally. The pivot support also 

 folds down, coming either over or under 

 the barrel of the gun. Four removable 

 rods, which are joined to the platform, 

 support the gun column when in use. 



A pipe extends from the compartment 

 to the water. This takes care of any 

 overflow which may enter when the gun 

 is in action. 



When folded away the gun takes but 



Pivot 

 Submarine deck-) 



Detail showing how 

 neatly and compactly 

 the gun and its support 

 are packed under deck 



little of the limited space 

 on a submarine, and thus 

 low-lying and protected 

 by a water-proof cover, it 

 offers no resistance to the 

 submerged travel of the 

 boat. In other words, 

 Becker boldly attacked 

 the problem of arming a submarine with a 

 weapon which could be raised or lowered 

 at will, as the vessel came to the surface 

 or submerged. 



*^Gun folded 

 under deck 



Magnetized Birds? Another Expla- 

 nation of Accurate Migratory Flight 



ONE of the many explanations that 

 have been offered to account for 

 the fact that migrating birds are able to 

 find their way by night and in cloudy or 

 foggy weather is that they are sensitive, in 

 some way, to currents of terrestrial 

 magnetism, and therefore direct their 

 flight by the magnetic meridians. This 

 suggestion was put forth by M. A. Thau- 

 zics, a French pigeon-fancier, who declares 

 that carrier-pigeons make poor flights 

 during the occurrence of magnetic storms. 

 He also asserts that the general use of 

 wireless telegraphy has diminished the 

 reliability of these birds to a surprising 

 extent. 



Those of us interested in science, engineering, invention form a kind of guild. We 

 should help one another. The editor of the POPULAR SCIENCE MONTHLY is 

 willing to answer questions. 



