Page:Popular Science Monthly Volume 91.djvu/128

 Protecting the British Fleets with Chain-Nets

No enemy submarine can thread the English Channel without being caught like a fish in a seine

��DISPATCHES from Europe tell re- peatedly that hostile submarines have been caught in nets, but none of them have indicated how it was done. The English fleet is kept in the Orkney Islands, protected by great steel chains woven in the form of simple nets which are not stationary but mobile. If they were anchored so that they could not be moved there is little doubt but that the industrious Ger- man commanders would find some way of getting through occasionally.

The nets covering the grand fleet are stretched out in great arms from the shores of the Islands, com- pletely covering the fleet. Various types of enemy vessels have come steaming up to these barriers, though of course under- water, in the effort to catch the great fleet happing. Whenever a daring commander has attempted such a coup he has always, so far, found himself not only nosing against a network of great chains but when he turned to run he has found himself in a circular net and doomed.

The British operations are simple. A sharp lookout, and probably electric look-

���There are a few loopholes in the nets, known to officials only, through which commercial vessels may pass in safety

��outs as well, keep the chain operators in- formed as to what is going on. When an enemy submarine enters the net its presence is soon known and the operators, taking the ends of the chain, draw it together to form a circle. The trap is then sprung. The British wait un- til something hap- pens- — until the sub- marine comes cau- tiously to the sur- face to look about, for there is nothing else that the com- mander can do. Once up he has the choice between destruction by shell or surrender, and to the credit of Germans it must be admitted that very often the commander refuses to surrender, hoping that some means of escape may still lie open.

The same sort of traps exist in the English Channel, where great chains are spread from the coast of France to the coast of England, with but a very few loop- holes which are known to British officers only, through which commerce may be carried on in safety. Every time a raider or a submarine cargo boat slips out of Germany it takes the northern passage. The channel is impossible to negotiate for any uninformed ship captain and it probably

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��A decoy ship leads a pursuing submarine into a circle of nets which immediately close up around it so that there is no escape

���Once enclosed by the chain of nets, the commander of the intruder faces destruc- tion from the shells or complete surrender

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