THE NATIONAL GEOGRAPHIC MAGAZINE 



89 



STORED LIKE GIANT EGGS IN A GIGANTIC CRATE 



A warehouse containing some of the 70,117 mines which were laid jointly by the British 

 and American mine-laying squadrons in the North Sea. Four-fifths of the mines were laid 

 by American ships. The actual casualties inflicted on the enemy submarine fleet probably will 

 never be known, but the Germans themselves are said to admit the loss of 23 undersea boats 

 in this area. The British admiralty staff hold that the surrender of the German fleet and the 

 armistice were caused largely by the failure of the submarine warfare (see text, page 109). 



19 1 7, the definite order was given to go 

 ahead. The Secretary of the Navy, Jo- 

 sephus Daniels, expressed the desire for 

 the best efforts of all who might be con- 

 cerned, and offered his own further ac- 

 tion or influence whenever needed. 



Cooperation in the fullest measure was 

 necessary from the start. Over 500 con- 

 tractors and subcontractors were soon 

 engaged in the manufacture of the many 

 parts, small and large, that go into the 

 make-up of a complete mine. 



Besides being a rush order all through, 

 the task was complicated by the necessity 

 for keeping parts of the mine secret. 

 Some pieces had to be made here and 

 others there and both kinds sent to a 

 third place to be joined, and all of the 

 parts were finally delivered at Norfolk. 

 Va., for shipment to Scotland, where the 

 complete mines were to be assembled 

 and adjusted, ready to plant. 



Such a manufacturing task would de- 

 mand the utmost care in ordinary times. 

 The hurry and pressure and disturbances 

 due to war conditions added many diffi- 



culties ; yet, so great was the interest and 

 so well was the operation's importance 

 understood, there was no halting nor 

 slighting of the work anywhere. 



A submarine mine of today consists of 

 a mine case, shaped like a ball or egg, 

 about one yard in diameter, and an 

 anchor in the form of an iron box about 

 two feet square, connected by a wire rope 

 mooring cable the size of one's little 

 finger. The mine case contains the 

 charge of high explosive — 300 pounds of 

 TNT in our mines — and the firing mech- 

 anism. 



When assembled, the mine case is 

 mounted on the anchor, the combination 

 standing about five feet high and weigh- 

 ing 1,400 pounds. The anchor has four 

 small wheels, like car wheels, to run on 

 steel tracks, and thus the mines may be 

 easily moved along the decks to the 

 launching point. 



WHEN THE MINE GOES OVERBOARD 



When the mine goes overboard, the 

 mine case floats on the surface, while the 



