Submarine Warfare of To-Day

would be something around 80 feet in length, with slow turning engines and a speed of 19 knots. I added that my preference was for the larger and slower type.

“He asked how many units of that class we could build in a year’s time, and I told him that I could guarantee fifty. He said that he would think the matter over, and we parted.

“A few days later I had another interview and was told that the British Government was ready to give us a contract for fifty vessels of the larger type, the whole lot to be delivered within a year’s time.

“On April 9th, 1915, the contract for fifty ‘chasers’ was signed.

* * *

“The Lusitania sailed on her last voyage May 1st, 1915, and a week later her torpedoing by a German U-boat was reported. My English friend was sailing that same day from New York, and we were giving him a farewell luncheon at Delmonico’s. When the appalling news was communicated to him he appeared much depressed, as indeed was natural enough, and also very thoughtful. Before he said good-bye he intimated to me that he intended advising the Admiralty to increase the number of ‘Chasers’; he asked me if I thought I could take care of a bigger order. I told him that I could guarantee to build a boat a day for so long a period as the Admiralty might care to name.

“After he reached England we shortly received a cablegram ordering five hundred additional ‘Sutphens,’ our code word for submarine ‘Chaser’; in other words we were now asked to build five hundred and fifty of these boats and deliver them in complete running order by November 15th, 1915.”

^{Fig. 2.—Plan of armed motor launch, showing internal arrangements. A. Officers’ sleeping cabin. B.B. Bunks. C. Cupboard. D. Lavatory. E.E. Stern petrol tanks. F. Wardroom. G. Table. H. Settee. I. Galley. J. Petrol stove. K. Engine-room. L.L. Main engines. M. Compressed air reservoirs. N. Auxiliary petrol engine driving dynamo, bilge pumps, fire pumps and air compressor. O. Electric storage batteries, switchboard and electrical starting arrangements for auxiliary engine. P. Chart-room with petrol tanks below. Q. Magazine. R. Fresh-water tanks. S. Forecastle. T. Bunks for crew. U. Forecastle lavatory. V. Watertight forepeak.}

The armament of a motor launch consisted of a 13-pounder quick-firing high-angle gun, capable of throwing a lyddite shell for over four miles, and was as useful against aircraft as it was against submarines. In addition to this heavy gun for small craft they carried about 1200 lb. of high explosive in the form of depth charges for bombing under-water craft, a Lewis machine gun, rifles and revolvers.

These vessels were driven by twin screws connected to twin engines of about 500 h.p. They possessed, in addition, an auxiliary petrol engine of about 60 h.p. for compressing the air required to start the main engines, for working the fire and bilge pumps, and for driving a dynamo to recharge the electric storage batteries. The triple tanks carried over 3000 gallons of petrol, and the consumption, when travelling at full speed, was a gallon a minute.

Many were fitted with wireless, and all of them had on board the most approved pattern of hydrophone, with which to listen below the surface for the movements of hostile submarines. They had electric light in the cabins and for navigation, fighting and mast-head signalling purposes. A moderately powerful searchlight, fitted with a Morse signalling shutter, was also part of their equipment.

These little miniature warships possessed a small wardroom and sleeping cabin for the officers, a galley with petrol range for cooking, an engine-room, magazine for the ammunition, chart-room, and ample forecastle accommodation for the crew of nine men. All parts of the ship were connected with the bridge by speaking-tubes and electric bells, and the aft deck accommodated a steel life-boat.

The duties of these craft varied considerably. For over three years they maintained a constant patrol in the North Sea, Atlantic, English Channel, Irish Sea, Mediterranean, Adriatic, Suez Canal, Straits of Gibraltar, and in West Indian waters. Only one who knows by experience can fully appreciate what work in these northern seas, with their winter snows and Arctic winds, and their chilly summer fogs, really means to a mere thirty tons of nautical humanity in as many square leagues of storm-swept sea infested with mines and hostile submarines. But when this book has been finished the reader will be in a position to judge for himself.

The losses of motor launches were not heavy considering the dangerous nature of their cargoes (3000 gallons of petrol within a few feet of 1500 lb. of high explosive in a wooden hull) and the duties they were called upon to perform in all weathers short of heavy gales. Several were blown up with terrible results to those aboard. Others caught fire and were burned—allowing only just sufficient time to sink the explosives aboard. A few were smashed to pieces on exposed coasts after struggling for hours amid heavy seas. One struck a mine off Ostend. Another was destroyed by shell-fire in the Mediterranean, and the part they played in the raids on Zeebrugge and Ostend, in which two were lost and a V.C. gained, is now world famous.

Coastal Motor Boats

There was, besides M.L.’s, another smaller but faster type of submarine chaser. These little vessels, of which there were about 80 actually in commission, possessed no cabin or other accommodation for long cruises. They were simply thin grey hulls with powerful high-speed engines. They were known as C.M.B.’s, or, to give them their full title, Coastal Motor Boats. The purpose for which they were constructed was to operate from coastal bases, and to be launched from ocean-going ships to chase a hostile submarine which had been located by seaplanes and reported by wireless in a given locality. This, however, was what they were intended for, but bore little relation to the work they actually accomplished. Their nickname was “Scooters,” and they certainly did “scoot” over the sea.

^{Fig. 3.—Diagram showing principal characteristics of a coastal motor boat (C.M.B.). Speed 50 miles per hour. A. Hydroplane hull, so constructed as to rise on to surface when travelling at full speed. B. Covered wheel-house. C. Navigating well. D. Wireless aerials. E. Depth charges (2 small size). F. Manhole to engine-room.}

There were three types of C.M.B.’s. One had a length of only 44 feet, and was intended for carriage on the decks of light cruisers or other moderate-sized surface ships. The armament was a Lewis machine gun and two depth charges for anti-submarine warfare. The next class were 55 feet in length and operated from coast bases. These were fitted with one or more Whitehead torpedoes, launched by an ingenious contrivance from the stern. Class III. were 70 feet in length, and were commissioned just before the signing of the Armistice. They were fitted for mine-laying close up to enemy harbours.

^{Fig. 4.—Plan of coastal motor boat, showing torpedo in cleft stern. A. Whale-back or arched deck. B. Wheel-house. C. Navigating well. D. Engine-room. E. Foreward petrol tanks. F. Forepeak. G. Depth charges. H. Cleft stern with torpedo ready for launching. I. Whitehead torpedo, launched stern first.}

The maximum speed of the 55-feet C.M.B.’s, which were the most numerous, was 40 knots, or nearly a mile a minute. They were driven by twin screws coupled to twin engines of 350 h.p. each—working at 1350 revolutions per minute. Being of very shallow draught, some 26 inches, these little vessels could skim, hydroplane fashion, over any ordinary mine-field, and a torpedo fired at them would merely pass under their keel. The risk of destruction from shell-fire was also reduced to a minimum by their small size and great speed. Their principal enemies were,