A large harbour for torpedo-boats and submarines has been enclosed by two long moles. Inside there is a miniature dockyard, with repair shops, magazines, stores, &c. Outside this harbour there is a safe anchorage for warships of great size. It is estimated that from beginning to end the naval works at Heligoland have cost Germany something like £10,000,000 sterling. Fortifications of remarkable strength have been erected. These consist chiefly of heavy guns, mounted in steel turrets, well concealed from the view of an enemy at sea, and so placed that every approach to the island is swept by their fire. As these guns are mounted on the plateau they have a high command, and attacking ships would have to encounter a plunging fire. Numerous bomb-proof control stations and magazines have been excavated. It is understood that, given an ample supply of ammunition and provisions, Heligoland is in a position to resist attack by the strongest naval force for an indefinite period. There is a powerful wireless station, a naval flying depot, and a large naval hospital. The garrison consists in the main of four companies of seamen gunners. The commandant is Rear-Admiral Jacobson. The high strategical importance of Heligoland is self-evident. Its position, some thirty-five miles from the mainland, is that of a strong outpost, defending the estuaries of the Elbe and Weser. A flotilla of destroyers or submarines based on the island could make things very uncomfortable for a fleet endeavouring to blockade the German coast, and it was the recognition of this fact which led to the construction of the new torpedo harbour. Thanks to the wireless station, communication can always be maintained with the mainland, and also by means of aircraft. In common with most military nations, Germany appears to place undue reliance on fixed defences as an element of sea power, but it is obvious, from the vast sums of money she has spent on its development, that Heligoland plays a leading part in the German plan of naval strategy. BORKUM. The island of Borkum came into prominence a few years ago as the result of an alleged case of espionage, in which two young British naval officers were concerned. Borkum is the first German island of the Frisian group. It commands the approach to the Ems, and would offer a convenient _point d’appui_ for naval operations against the German coast. This, apparently, explains why it has been strongly fortified by the Germans. Its guns are said to be numerous, and are well placed among the lofty sand dunes which are a feature of the island. The garrison is supplied by the army, and includes some batteries of field artillery and machine guns. The experience gained during naval manœuvres has shown that Borkum would be a difficult place to surprise. According to report, some of the guns in position are powerful enough to inflict serious damage on the largest warships. EMDEN.