n submarines, but the latest boats completed
before the war were vessels of 900 tons displacement with heavy-oil
engines of 2000 H.-P. and electric motors of 900 H.-P., possessing a
surface and submerged speed of 18 and 10 knots respectively and a
cruising radius of 4000 miles. They had four torpedo tubes for eight
torpedoes, two 14-pdr. quick-firing guns, and two 1-pdr. high-angle
anti-aircraft guns. Naturally they were also equipped with all the
latest improvements, such as wireless apparatus, panoramic
periscopes, armoured conning-towers, and decks. Since the outbreak
of the war the Germans have built even more powerful submarine boats
whose perfections in regard to speed, radius of action and armament
became known through their accomplishments. Of these we will hear
more in a later chapter.

At just what period of the war the Germans woke up to the vital
importance to them of an enormous submarine fleet is not known. It
may have been immediately upon the amazing exploit of Captain
Weddigen in the North Sea. At any rate the war had not long
progressed before the destruction caused by German submarine attacks
began to awaken the apprehension of the Allies and neutral nations.
Retaliation in kind was impossible. The Germans had neither
merchant nor naval ships at sea to be sunk. The rapidity with which
the volume of the loss inflicted upon merchant shipping grew
indicated an equally rapid increase in the size of the German
underwater fleet. Neutrals were enraged by the extension by the
Germans of the areas of sea in which they claimed the right to sink
neutral ships, and their growing disregard for the restraining
principles of international law. How greatly they developed the
submarine idea was shown by their construction in 1916 of vessels
with a displacement of 2400 tons; a length of 279 feet, and a beam
of 26 feet; a surface speed of 22 knots, cruising radius of 6500
miles, mounting 4 to 8 guns and carrying a crew of from 40 to 60.
But it was reported that two vessels designed primarily for surface
cruising, but nevertheless submersible at will, had been laid down
of 5000 tons, a length of 414 feet, and a radius of 18,000 to 20,000
miles. These "submersible cruisers" as they were called, mounted 6
to 8 guns, 30 torpedo tubes, and carried 90 torpedoes. What part
vessels of this type shall play in war is still to be determined.

Of the smaller naval powers, Italy comparatively early had become
interested in the bu