AFTER BIG "FISH."

Poverty Bay Herald, Volume XLIV, Issue 14286, 1 May 1917, Page 6

AFTER BIG "FISH."

HUNTING DOWN THE SUBMARINE

PIRATES,

HOW THE TRAWLERS WORK,

1 am coufideut that it is because the Admiralty has driven the submarines from the home waters that Germany announced . her intention to create a wider zone (says Alfred Noycs in one of his '.submarine articles). We have 4000 private yachts, whalers, and fishing- j vessels, and 60,000 men in the anti-sub- ' marine fleet. Every boat is armed with guns throwing 12 or 14-pound explosive shells, and has 1000 yards of steel netting trailing behind. We have destroyed 200 submarines. All the home waters ! are mapped out in blocks and every block patrolled. Four thousand ships and sixty thousand men! Nor is this; all, for these figures include only tho : so-called patrol or trawler fleet gathered to protect the English Channel and the waters around the British Isles. In. addition to this, large fleets of minelayers place mines in the entrances of German harbours, while the submarines are away, and prevent them from returning. There are numerous esquadnlles of aeroplanes, manned by the French; the constabulary constantly search the shores of the. British Isles t'o ferret out the concealed submarine bases, and lately, at least, the skippev of every armed merchantman is, upon occasion, a submarine hunter. | NETTING TIN FISH, I Many of the skippers of these trawlers and patrol-boats are Scotchmen. In faat, there are between 60,000 and 70,000 fishermen who have already been uniformed, trained', and practised, even in gunnery, for anti-submarine service. Many of them are Scotch, and all arc seamen who range in age from the twenties to the three, scores and tens. Yes, some of them are even as old as that, but they are the hardiest set of men I ever saw. I as"ked one old fellow how he stood the extreme cold, and he replied that he, like the rest, soaked his seaboots and gloves in the water. Really, they believe the water is warmer than the air. and perhaps they arc right. • I It was one of these old chaps who told! me how he .had! been "shooting his net"— that's the term they use for dropping one of their nets into position. . They throw off a heavy buoy to which ( one end of the net is made fast, and then steam away, paying out the net a»s they go. \Vhen "several are in a gi-oup all pay out their nets in this way, and then each trawler "takes up the buoy of the adjoining vessel, so that the* nets are stretched between the boats at intervaJs of 1000 or 1500 yards, depending upon the width of the net. The weighted nets sink to the bottom, and the line of trawlers, by steaming ahead in unison, can sweep the sea behind them for whatever width they desire, the. only necessity being that sufficient ships join the line to give this width. I once, saw the nearer units of a line of which* I was told, comprised' sixty trawlers and stretched 1 from the English shore to the Irish,: shore across the" Irish sea-. Well, this old chap had no more than got his net shot. than he felt a jerk in it . that threw him six points off his course. A submarine had become entangled in the net. "How did you get rid of it?" I deI mo nded. v . Said he: "I caiina tell ye juist what happened, bu€. it was what the A'miralty meant should happen when one o" 1 these undersea lads gets entangled in our nets. And. mind ye, the nets are verra expensive." TRAILING THE QUARRY. How submarine? are located, and captured 1 is told by Captain William S. Simms, the United States naval observer, in an articles in the Philadelphia "Public Ledger." The U-boat is forced to come to the surface at least once a day to fill her air-tanks and recharge her storage batteries, for the gasoline engines cannot be used when submerged. Both these operations make a good deal of noise, which is often heard by a patrol near by. As sqon as the submarine perceive she has .been sighted, he says, she has got to submerge. The commander of the patrol-boat sends out a Avireless saying that at such and such a, time — say, 7.30 o'clock in the morning — the submarine was at a certain place. An , hour later, allowing for its maximum submerged speed (not ' ove** twelve miles an hour) it cannot be outside of a certain definite area, no matter in what direction it may be running. By 9.30 it cannot be outside of a certain larger area. The commander of the patrol-flotilla deploys his boats accordingly. At the same time aeroplanes go out and look for signs of the submerged submarine. The latter, though under water, is not wholly hidden. A moving body of that size makes some disturbance at the surface. The surface waves are of a certain regularity, which is perceptibly disturbed by the submarine, even though she be as far as 150 feet below — that being about the limit of depth to which she could venture, lest the pressure of the water crush) her. The man in the aeroplane is able to overlook a very large expanse of seasurface. As soon as he perceives the "ripple" of a submarine he signals the nearest, patrol-boat. 'and the latter proceeds to lower a net in front of the submarine. The latter, of course, while under water, is blind. It does not know that if has been located ; it does not know what is going on overhead on the surface of the sea. Tt is groping its way through darkness by compass. ' But the submarine, thus detected in its underwater . travel, can be easily followed. The direction "of its course is plainly seen. To drop a net in front of it is a simple performance. The undersea-boat pokes her nose into it— through one of the meshes — and is Caught, like; a) fish in a gill-net. The business is just a kind of fishing. Once the submarine is 'caught in a net it has small hope of escape, for the nets used are of special construction,, and even the latest U-boat models, whicJi have shaped' prows for net-cutting, are rarely, able to break a-way. The net used for -the purpose is much like a fishing net; but it is made of piano-wire (instead of cord, and its meshes are about ten feet square. It is about three hundred yards Jong and a hundred feet deep, with floats to uphold the upper edge, and leaden sinkers along the lower edge t<J maintain it in a vertical position, like a fence. The' wire being so small (though very strong) and the meshes so large, a net of the, size described can be rolled 1 up into a bundle !pf no great bulk arid 1 rapidly stowed, iii the patrol-boat. The net. when once the submarine encounters it, furnishes an elastic barrierincomparably more difficult to penetrate on that account. In fact, because it yields, it can not be penetrated.- H yields, yet holds*. Meanwhile; the floats on the surface attached to the net, show | by their movement the struggles of the, submarine/ to escape. If some of the floats sink it is manifest that the trapped; boat .is trying to get away by sinking and passing beneath tho net. But such an effort rarely, if ever, succeeds. The netted submarine may sulk and refuse to" come to the .surface. That doesn't matter at all. If those on board prefer to die for lack' of air, it is up to them to decide. But experience has proved that they invariably prefer to come up aod surrender before their airfiiipply gives out. In their 'enoe, ' I lit* captors are content to wait.