The following facts, which, were given to the writer by Captain (now Admiral) von Essen of the Russian Navy, at the close of the Russo-Japanese war, and were published in the "Scientific American," serve to show what great powers of resistance are conferred on a warship by the system of subdivision above described. The story of the repeated damage inflicted and the method of extemporised repairs adopted, is so full of interest that it is given in full: "Immediately after the disaster of the night of February 8th," when the Japanese, in a surprise attack, torpedoed several of the Russian ships, "the cruiser _Pallada_ was floated into drydock, and the battleships _Czarevitch_ and _Retvizan_ were taken into the inner harbour, and repairs executed by means of caissons of timber, built around the gaping holes which had been blown into their hulls by torpedoes. The repairs to the _Pallada_ were completed early in April, and about the 20th of June the _Czarevitch_ and _Retvizan_ were also in condition to take the sea. On the 13th of April, during the sortie in which the _Petropavlovsk_ was sunk with Admiral Makaroff on board, the battleship _Pobieda_, in returning to the harbour, struck a contact mine, and was heavily damaged. Similar repairs were executed, and this ship was able to take her station in the line in the great sortie of August 10. "On June 23 Captain von Essen's ship, the _Sevastopol_, was sent outside the harbour to drive off several Japanese cruisers that were shelling the line of fortifications to the east of Port Arthur. This she accomplished; but in returning she struck a Japanese mine, which blew in about 400 square feet on the starboard side, abaft the foremast, at a depth of about 7 feet below the water-line. The rent was from 7 to 10 feet in depth and 35 to 40 feet in length. The frames, ten in all, were bent inward, or torn entirely apart, and the plating was blown bodily into the ship. She was taken into the inner harbour, where the injured portion of the hull was enclosed by a timber caisson in the manner shown in the engravings on page 155. The caisson--a rectangular, three-sided chamber--was built of 9-in. by 9-in. timbers, tongued and grooved and carefully dovetailed. The floor of the caisson abutted against the bilge keel. The outer wall, which was at a distance of about 10 feet from the hull, had a total depth of about 34 feet, the total length of the caisson being about 75 feet. Knee-bracing of heavy timbers was worked in between the floor and the walls, and the construction was stiffened by heavy, diagonal bolts, which passed through from floor to outside wall, as shown in the drawing. Watertight contact between the edge of the caisson and the hull of the ship was secured by the use of hemp packing covered with canvas. The whole of the outside of the caisson was covered with canvas, and upon this was laid a heavy coating of hot tar.