"7.45 A.M., March 24th, 1918; 'E 44' (Lieut. Venning): Five battleships (apparently of _Kaiser_ class) and a destroyer (the latter zigzagging). Turned to attack on surface. The destroyer turned towards me and fired a white Very's light. His range was about 2000 and the big ships 4000 yards. All ships then altered course. 7.50 A.M.: dived at full speed. Hit bottom hard at 64 feet, and proceeded along bottom at full speed. 7.53: one depth-charge exploded astern. 7.55: another depth-charge exploded astern. I stopped engines. 8.5 A.M.: went ahead 6 knots. 8.10: destroyer passed overhead, and the sweep-wire was heard scraping over the 'jumping wire.' 9.30 A.M.: eased to four knots. Sounds of propellers died away. Under-water explosions were heard at intervals till 11 A.M." If this chance had been given, in such shoal water, to a British destroyer screen, the submarine would certainly not have been so calm about it. There are some first-hand reports on our own depth-charges:-- Submarine "D 7," February 10th, 1918 (Lieut. Tweedy), suddenly sighted H.M.S. _Pelican_ through her periscope. She increased to full speed and went down deeper, altering course from north to west. "3.48 P.M.: First explosion occurred, loud and violent, but no damage or inconvenience. Very shortly afterwards a second explosion. This was considerably more violent, shattering several lights and flooding the after-periscope. Heavy shock throughout the boat, but no serious damage. Order was given to 'blow externals.' While rising, a third explosion occurred of about the same intensity as the first. On breaking surface made recognition signals...." The comment of authority on the incident blandly points out that by more accurate judging of speeds, distances, etc., the estimated distance of 150 yards between "D 7" and the second depth-charge could have been much reduced and better results obtained. There is, of course, no hint that the destroyer was to blame in the matter of recognition. In all these cases it is the destroyer's duty to take it for granted that any periscope is hostile, and the comments on these reports usually show some sympathy with the surface ship's natural disappointment at finding she has attacked one of her own side. On 29th Feb. 1918, submarine "L 2" (Lieut.-Commander Acworth) had a similar experience, which had very little that was amusing about it. Her opponents were the United States' destroyers _Paulding_, _Davis_, and _Trippe_. "... I lowered periscope and dived to 90 feet. Gun-shots being heard, I proceeded at full speed to 200 feet, at which depth the first heavy depth-charge exploded, and at the same time the after-hydroplanes jammed hard-up. We now took a tremendous inclination by the stern, the tail touching the bottom at 300 feet.