I must recall to the reader's mind the description of the entrance channel of the canal. It was shown in Part I, Chapter II, how very narrow the navigable channel had become owing to the silting of the sand, and how rapidly the latter process would accentuate the obstructive quality of a sunken vessel. It was also shown why the channel at the shore end of the two curved piers was the ideal position at which to place the blockships. Intrepid and Iphigenia had been sunk by us exactly at their selected positions. Each vessel spanned right across the dredged channel, and therefore blocked it effectually. For the first time in naval history a blocking operation had been carried out successfully in the face of up-to-date defence measures.
Some of the photographs, taken at high tide, appear to show sufficient space through which vessels could pass on either side of the blockships. But the presence of water does not signify the presence of sufficient water to float such craft as submarines and destroyers even at high tide. Two other photographs show clearly that the ends of the vessels were practically on the edges of the sandbanks.
The Work of Salvage
The Germans, as prompt in propaganda as they were unenterprising in sea-fighting, at once published a communiqué to the effect that the operation had utterly failed, adding that the blockships had been sunk by the German batteries before reaching their goal. Curiously enough, their official statements were strangely silent on the subject of prisoners. They also averred that the attack on the Mole had been driven back. Not content with these "terminological inexactitudes," they went so far as to take a photograph to prove their contention. The photograph was taken with the camera pointed inland. The land was eliminated from the background in the original so as to give the impression that the camera was pointing out to sea. A line was drawn between, and parallel to, the blockships and marked "The line of the channel," whereas it was a line nearly at right angles to the channel. Words were added to the effect that the photograph proved clearly that the channel was not blocked, and copies of the photograph were circulated all over Germany and neutral countries. What wonderful liars!—but clumsy! The amusing part of it was that we knew the German naval authorities reported "Zeebrugge is blocked" to their craft stationed elsewhere, and, further, our airmen obtained photographs day after day showing some twenty-three torpedo craft and twelve submarines bottled up at Bruges.
From the morning after the operation until the Germans finally evacuated Zeebrugge, our aerial bombers dropped, on the average, four tons of bombs daily on that place. Our special measures with regard to constructive work in each blockship, designed to hamper the work of salvage, must have presented the enemy with a formidable problem. The work of clearing the channel was certainly not assisted by the dropping of bombs upon the salvors. To what extent the Germans attempted to remove the vessels is unknown to me, but we do know well enough that none of the three was moved a foot nor were they cut away to allow vessels to pass over them. Thanks to our airmen, we knew, almost from hour to hour, what measures were being taken to dredge a new channel. I believe that no torpedo craft or submarines could use the exit for a considerable time, and that about five months elapsed before they could enter or leave the canal at any other period than the top of high tide.
Having contrived that each blockship should embody all the main obstacles to salvage work, we were more or less confident that, if once placed in position, these ships could not be easily removed. Subsequently, at the earliest opportunity, our own salvage service commenced their endeavours to clear the canal. In January, 1921, two years and three months after Zeebrugge was again in the hands of the Allies, the last of the three blockships was moved sufficiently to enable the channel to be used with freedom. A great amount of labour and money had already been expended, but still further efforts were required before the canal could be altogether freed from obstructions. One may certainly remark that the canal was "well and truly blocked."
Information reached us afterwards that the Kaiser personally visited Zeebrugge shortly after the operation so that he could discover the actual truth for himself. What his remarks were on arrival is not known to me, but a photograph in my possession, taken on that occasion, certainly does not give him an air of affability.
The Reckoning
The main material result, then, was that the canal was blocked and that the services of twelve submarines and twenty-three torpedo craft were unavailable for a considerable period. As long as the canal remained blocked, German submarines detailed for operating against Allied commerce in the English Channel and other waters outside the North Sea were, for the most part, compelled to do so from the Heligoland Bight. This increased the length of voyage to and from their areas of operation and consequently reduced the duration of their stay in such waters.