These charges deserve a eulogy of their own. They have done more towards winning the war than all the giant howitzers whose calibre has stupefied the world. In appearance and mechanism they are the simplest of affairs. The Navy always refers to them as cans: "I dropped a can right on his head"; "it was the last can that did the business." Imagine an ash can of medium size painted black and transformed into a ponderous thick walled cylinder of steel crammed with some three hundred pounds of T.N.T. and you have a perfect image of one. Now imagine at one end of this cylinder a detonator protected by an arrangement which can be set to resist the pressure of water at various levels. A sub appears, and sinks swiftly. If it is just below the surface, the destroyer drops a bomb set to explode at a depth of seventy feet. The bomb then sinks by its own weight to that level at which the outward force of the protective mechanism is over-balanced by the inward pressure of the water; the end yields, the detonator crushes, the bomb explodes, and your submarine is flung horribly out of the depths almost clear of the water, and while he is up, the destroyer's guns fill the hull full of holes. Or suppose the submarine to have gone down two hundred feet. Then you drop a bomb geared to that depth upon him, and blow in his sides like a cracked egg. The sound of these engines travels through the water some twenty or twenty-five miles, and there have been ships who have caught the vibration of a distant depth bomb through their hulls and thought themselves torpedoed. I once saw a depth bomb roll off a British sloop into a half filled dry dock; the men scrambled away like mad, but returned in a few minutes to fish out a "can," that had sixty more feet to go before it could burst. It lay on the bottom harmless as a stone. The charges rest at the stern of a vessel, lying one above the other on two sloping runways, and can be released either from the stern or by hydraulic pressure applied at the bridge. The credit for this exceedingly successful scheme belongs to a distinguished American naval officer. The destroyer has but one deck which is arranged in the following manner. I take one of the "thousand tonners" as an illustration. From an incredibly lean, high bow, a first deck falls back a considerable distance to a four-inch gun; behind the gun lies another open space closed by a two-storied structure whose upper section is the bridge and whose lower section a chart room. At the rear of this structure the hull of the boat is cut away, and one descends by a ladder from the deck which is on the level of the chart room floor, to the main deck level some eight feet below. Beyond this cut but one deck lies, the mere steel covering of the hull. Guns and torpedo tubes are mounted on it, the funnels rise flush from the plates; a life line lies strung along its length, and strips of cocoa matting try to give something of a footing.