The autumn of 1915 witnessed the introduction of mine-laying submersibles. The trotyl-filled cylinders were dropped on recognized trade routes without the slightest regard for the rights of neutrals. The mines were kept in a special chamber, ingeniously contrived so that it could be flooded without the water entering elsewhere, and released through a trap-door. Thus another weapon was added to the submarine’s armoury. It answered all too well. “They can follow your mine-sweeper,” said Sir Edward Carson, “and as quickly as you sweep up mines they can lay new ones without your knowing or suspecting.” In 1914 the enemy had only one means of sowing these canisters of death, namely, by surface vessels. It will be recollected that the Königin Luise was sunk in the North Sea on the morning of the 5th August while on this hazardous duty. Germany’s opportunity for hurting us in this manner was of short duration. The British Navy asserted itself, with the result that the enemy was perforce compelled to find a new method. He resorted to the use of specially fitted submarines.

In due course 4.1–in. guns, mounted on disappearing platforms, made their début, followed by U-boats provided with two 5.9–in. guns. With increase of gun-power came a necessary increase in size, and with both several distinct advantages and disadvantages. The boats were less easy to manœuvre, required augmented crews, and offered a larger area for attack. Against these minus qualities must be set those of increase of cruising range, and the possibility of spoil, the sole excuse of the old-time pirate. Hitherto his more scientific successor could only sink his victim. Now, given favourable conditions, he might carry off goods useful to the Fatherland. One German U-boat secured twenty-two tons of copper from merchantmen destroyed during a 5000–mile cruise.

Germany waxed particularly enthusiastic over her diving cruisers. These boats displaced 5000 tons, were from 350 feet to 400 feet long, had a much accelerated submerged and surface speed, were protected by an armour belt of tough steel plate, and mounted a couple of 5.9–in. guns. Some of these submersibles seem to have been driven by steam when in surface trim, others by the usual Diesel engines. On the 11th May, 1918, a British Atlantic escort submarine came across one of these fine fellows travelling awash, likely enough anxious to have a shot at the merchant convoy which the representative of His Majesty’s Navy was on her way to pick up. A heavy sea was running at the time, but at intervals between the waves the periscope revealed the position of his rival to the British commander. One torpedo sufficed. The Tauchkreuzer went down, carrying with her the sixty or seventy men who constituted her company. There were no survivors. She had the distinction of being the first of the type to be destroyed.

Germany’s merchant service, prizes of war, or driven off the seven seas and growing barnacles in neutral or home ports, virtually ceased to exist at the outbreak of hostilities. The mammoth liners which formerly competed with our own no longer sailed the seas with their holds full of cheap goods and their saloons alive with travellers bent on ‘peaceful penetration’—and other things. It rankled in the bosoms of her shipping magnates that the much-vaunted High Sea Fleet was impotent to prevent Britain ‘carrying on’ commercially while conducting campaigns in all parts of the world. It was true that Germany’s U-boats were making inroads on the maritime resources of her enemy, that when hostilities were over they might compete on more than even terms because of these losses, but to-day rankled though to-morrow was full of hope. Likewise the Economic Conference in Paris had declared its firm intention to impose special conditions on German shipping after the war. After the war! The Director-General of the North German Lloyd Line said that the English were not so unpractical as to reject a favourable freightage or passage.

I cannot give you the name of the man or woman who first suggested the possibilities of the submarine for business purposes. The idea was certainly not a particularly novel one. All I can say definitely is that the concern which owned the pioneer vessels was called the Ocean Navigation Company, and that the president was Herr Alfred Lohmann. If British merchantmen could use American ports, why not German commercial submarines? The Deutschland was built with this object in view. Officially she was described as “a vessel engaged in the freight trade between Bremen and Boston and other Eastern Atlantic ports.”

She left Heligoland on the 23rd June, 1916, and arrived at Norfolk News, Virginia, seventeen days later. The German Press quite naturally went into ecstasies over the achievement. Yet it was not quite such a unique event as they imagined. Ten submarines built in Montreal had crossed the Atlantic nine months before. The Deutschland duly discharged her cargo, stayed three weeks or so, and returned to Germany. The Kaiser showed his pleasure by conferring decorations on Herr Lohmann and the crew. Germany was again a maritime nation—of sorts.

The submersible had travelled no fewer than 8500 nautical miles. She made a second voyage to America in October. This time her port of arrival was New London, Connecticut. When starting on her return journey she managed to get in collision with one of the escorting tugs, which sank with the loss of seven of her crew. The Deutschland was the pioneer of seven similar boats said to be in course of construction. A sister vessel, the Bremen, was launched and started on a voyage. She is now some two years overdue.

Official Germany revealed no great faith in the possibilities of the commercial submarine, though this does not necessarily mean that the autocrats of the Wilhelmstrasse showed their real belief. It sometimes suited them to lie. According to the Frankfurter Zeitung, £15,000,000 per annum was earmarked for the fostering of Germany’s moribund merchant service in the next decade.

In October 1916 the depredations of U 53 off the American coast were hailed by the population of Berlin and other German towns as a sure prelude to peace. She was the first armed U-boat to cross the Atlantic, but the German nation saw her multiplied by scores, if not by hundreds. Many optimistic folk held the belief, based on the wonderful tales that were told of huge Allied shipping losses, that the war would be over before the dawn of a new year. Britons are not the only people who have hugged delusions. After having put in at Newport News for a few hours and been visited by various notabilities, U 53 took up a position off the Nantucket Lightship, so well known to all Atlantic voyagers. She then calmly proceeded to sink half a dozen ships—British, Dutch, and Norwegian—under the nose of U.S. destroyers. According to accounts that were published in American newspapers at the time, the submersible had four torpedo-tubes, one 4–in. gun forward and one 3–in. gun aft, three periscopes, wireless apparatus, and engines of 1200 h.p. that enabled her to travel on the surface at eighteen knots. Her submerged speed was understood to be some four knots less.

U-boats were built at the Vulkan and Blohm and Voss shipyards of Hamburg; at Hoboken, in the former yards of the Société John Cockerill;[[20]] at Puers, near Termonde; and at the great naval bases of Kiel and Wilhelmshaven. Here the parts were assembled, for it is fairly evident that the thousand and one units of a modern submersible were constructed on many lathes in many parts of the Fatherland. For example, it is believed that UC 5, the small mine-layer of 200 tons displacement captured by the British Navy and exhibited off the Thames Embankment, was brought in sections to Zeebrugge and put together there.