The principal reason for this is that the blunt-nosed air-bomb, no matter from how high it may be dropped, has neither the velocity nor the structure to penetrate the enclosed spaces of a ship where its explosive charge would find something to exert itself against. This is why an 18-pounder shell, penetrating to a casemate or engine-room, for instance, may easily do more damage to a warship than an air-bomb of ten times that weight expending its force more or less harmlessly upon an upper deck. Merchant ships, with their inflammable and comparatively flimsy upper works, are more vulnerable to air-bombs than are warships, but even of these very few indeed have been completely destroyed as a consequence of aerial attack. Some of the gamest fights of the war on the sea have been those of merchant skippers who, in the days before their ships had guns of any description to keep aircraft at a distance, brought their vessels through by the exercise of the boundless resource which characterises their kind, usually by sheer skill in manoeuvring. A very remarkable instance of this character I heard of a few days ago from a Royal Naval Reserve officer who figured in it. "I was in a British ship temporarily in the Holland-South American service at the time," he said, "and we were outward bound from Rotterdam after discharging a cargo of wheat from Montevideo. It was before the Huns had raised any objection to ships bound for Dutch ports using the direct route by the English Channel, and also before the U-boats had begun to sink neutrals on that run. Except for the comparatively slight risk of encountering a floating mine, we reckoned we were just about as safe in the North Sea as in the South Atlantic. Of course, we carried no gun of any kind--no heavy gun, I mean. We _did_ have a rifle or two, as I will tell you of presently. "Why the attack was made we never had any definite explanation. In fact, the Germans themselves probably never knew, for they tumbled over themselves to assure the Holland Government that there was some misunderstanding, and that they would undertake that nothing of the kind should occur again. "My personal opinion has always been that it was a sheer case of running amuck on the part of the Hun aviator responsible for the outrage; for, as I have said, we were empty of cargo, our marks were unmistakable, and we were steering a course several points off the one usually followed by the Dutch boats to England. Anyway, he paid the full penalty for his descent to barbarism. "It was a clear afternoon, with a light wind and lighter sea, and we were steaming comfortably along at about nine knots, heading for the Straits of Dover, when the look-out at the mast-head reported a squadron of 'planes approaching from the south.