The viaduct of the mole was to be blown up by two submarines, CI (Lt.
Ostend, though the width of the entrance was reduced probably to 300 ft., was not closed, and though the ships sunk in Zeebrugge must have caused great inconvenience and delay it may be doubted whether they actually stopped the passage of submarines for more than a month.
In the present article, periscopes for land service and those forming part of the equipment of submarines will be described in turn.
The German battle cruiser " Goeben " eluded the British Mediterranean fleet and got safely into the Sea of Marmora; three British cruisers were sunk by submarines in the North Sea; and a British squadron under Adml.
On the other hand, German sporadic attacks by sea and air on British watering places and the increasing activity of German submarines gave Mr. Churchill and the Admiralty much concern.