It was about 5 p.m. that I saw two trawlers ahead, one on each bow. By this time the boat's crew had quite recovered, but I did not wish to dive, as the battery was still pitiably low. I gradually altered course to north-east, but after half an hour's run I almost ran on top of a group of patrols in the dusk.
I crash-dived, and they must have seen me go down, as a few minutes later the boat was violently shaken by a depth-charge.
We were at twenty metres, still diving at the time. I consulted the chart, but could find no bottoming ground within fifty miles, a distance which was quite beyond my powers.
At 11 p.m. I simply had to come up again and get a charge on the batteries.
From 7 p.m. to 10 p.m., at regular half-hourly intervals, a depth-charge had gone off somewhere within a radius of two miles of me. Needless to say, I was only crawling along at about one knot and altering course frequently. What was so terrible was the patent fact that the patrols in this area had evidently got some device which enabled them to keep in continual touch with me to a certain extent.
These monotonous and regular depth-charges seemed to say: "We know, Oh! U-boat, that we are somewhere near you, and here is a depth-charge just to tell you that we haven't lost you yet." [[17]]
[17.] Karl was quite right; it is evident that he had the misfortune to encounter one of our new hydrophone-hunting groups, just started In the Fair Island Channel. The incident of the depth-charges every half-hour was known as "Tickling up." Probably the patrol only heard faint noises from him.--ETIENNE.
As an hour had elapsed since the last depth-charge, I felt fairly happy at coming up, and on making the surface I was delighted to find a pitch-black night and a considerable sea. From 10 p.m. to 1 a.m. I actually had three hours of peace, and in this period I managed to cram a considerable amount of stuff into the batteries. The densities were rising nicely and all seemed well, when I did what I now see was a very foolish thing.
I made my 1 a.m. wireless report to Nordreich, in which I requested orders at 3 a.m. and reported my position, together with the fact that I had been badly hunted.
In twenty-five minutes they were on me again! I had most idiotically assumed that the English had no directional wireless in these parts. They have. They've got everything that they have ever tried up there; it was concentrated in that infernal Fair Island Channel.