I have already said that a great part of the destroyer's duty was to rescue merchantmen that were being attacked by submarines: this _Luckenback_ incident vividly illustrates this point. Had the submarine used its torpedo upon this vessel, it probably would have disposed of it summarily; but it was the part of wisdom for the submarine to economize in these weapons because they were so expensive and so comparatively scarce, and to use its guns whenever the opportunity offered. The _Luckenback_ was armed, but the fact that the submarine's guns easily outranged hers made her armament useless. Thus all the German had to do in this case was to keep away at a safe distance and bombard the merchantman. The U-boat had been doing this for more than three hours when the destroyer reached the scene of operations; evidently the marksmanship was poor, for out of a great many shots fired by the submarine only about a dozen had hit the vessel. The _Luckenback_ was on fire, a shell having set aflame her cargo of cotton; certain parts of the machinery had been damaged, but, in the main, the vessel was intact. The submarine was always heroic enough when it came to shelling defenceless merchantmen, but the appearance of a destroyer anywhere in her neighbourhood made her resort to the one secure road to safety--diving for protection. The _Nicholson_ immediately trained her guns on the U-boat, which, on the second shot, disappeared under the water. The destroyer despatched men to the disabled vessel, the fire was extinguished, necessary repairs to the machinery were made, and in a few hours the _Luckenback_ had become a member of the convoy.
Hardly had she joined the merchant ships and hardly had the _Nicholson_ taken up her station on the flank when an event still more exciting took place. It was now late in the afternoon; the sea had quieted down; the whole atmosphere was one of peace; and there was not the slightest sign or suggestion of a hostile ship. The _Orama_, the British warship which had accompanied the convoy from its home port as ocean escort, had taken up her position as leading ship in the second column. Without the slightest warning a terrific explosion now took place on her starboard bow. There was no mystery as to what had happened; indeed, immediately after the explosion the wake of the torpedo appeared on the surface; there was no periscope in sight, yet it was clear, from the position of the wake, that the submarine had crept up to the side of the convoy and delivered its missile at close range. There was no confusion in the convoy or its escorting destroyers but there were scenes of great activity. Immediately after the explosion, a periscope appeared a few inches out of the water, stayed there only a second or two, and then disappeared. Brief as was this exposure, the keen eyes of the lookout and several sailors of the _Conyngham_, the nearest destroyer, had detected it; it disclosed the fact that the enemy was in the midst of the convoy itself, looking for other ships to torpedo. The _Conyngham_ rang for full speed, and dashed for the location of the submarine. Her officers and men now saw more than the periscope; they saw the vessel itself. The water was very clear; as the _Conyngham_ circled around the _Orama_ her officers and men sighted a green, shining, cigar-shaped thing under the water not far from the starboard side. As she sped by, the destroyer dropped a depth charge almost directly on top of the object. After the waters had quieted down pieces of débris were seen floating upon the surface--boards, spars, and other miscellaneous wreckage, evidently scraps of the damaged deck of a submarine. All attempts to save the _Orama_ proved fruitless: the destroyers stood by for five hours, taking off survivors, and making all possible efforts to salvage the ship, but at about ten o'clock that evening she disappeared under the water. In rescuing the survivors the seamanship displayed by the _Conyngham_ was particularly praiseworthy. The little vessel was skilfully placed alongside the _Orama_ and some three hundred men were taken off without accident or casualty while the ship was sinking.