"Generally speaking," he said, reaching up the match with which he had just lighted a cigarette to rekindle the tobacco in my expiring pipe, "the rôle of the M.L. is very much more defensive than it is offensive. It is supposed to police certain waters, watch for U-boats, report them when sighted, and then carry on as best it can till a destroyer, or sloop, or some craft with a real punch in it, comes up and takes over. Well, my idea from the first has been to make that 'defensive' just as 'offensive' as possible, and it's really astonishing how obnoxious some of us have been able to make ourselves to the Hun. Off-hand, since, with his heavier guns, the average Hun is more than a match for us even on the surface, there wouldn't seem much that we could do against him beyond running and telling one of our big brothers. The perfecting of the depth-charge gave us one very formidable weapon, however, and that of the lance-bomb another, though the days when Fritz was tame and gullible enough to allow himself to be enticed sufficiently near to permit the use of the latter are long gone by. The most satisfying job I ever did, though, was pulled off with a lance-bomb; and, since there is not one chance in a thousand of our ever getting away with the same kind of stunt again, there ought to be no kick on my telling you just how it happened. "You see," he went on, pulling a big furry-backed mitten on the hand most exposed to the cold in gesticulation, and tucking the fingers of the other inside the neck of the Balaclava for warmth, "Fritz is an animal of more or less fixed habits, and so the best way to hunt him, like any other animal, is to begin by making a study of his little ways. I specialised on this for some months, confining myself almost entirely to what he did in attacking, or when being attacked by, M.L.s, and ignoring his tactics with sloops, trawlers, and other light craft. It wasn't long before I discovered that his almost invariable practice--when it was a matter of only himself and a M.L.--was to get the latter's range as quickly as possible, endeavour to knock it out, or at least set it afire, by a few hurried shots, and then to submerge and make an approach under water for the purpose of making a closer inspection of the damage inflicted. In this way the danger of a hit from the M.L.'s gun was reduced to a minimum--an important consideration, as a holing by even a light shell might well make it impossible to submerge again. And a U-boat incapable of seeking safety in the depths is, in any part of the North Sea where it would have been likely to meet a M.L., just as good as done for.