By the aid of a piece of flexible tubing lined with indiarubber the broken portions of the petrol pipe were temporarily reunited. The next step was to plug the holes in the tank. This task was performed by means of a metal instrument consisting of a metal rod of about a third of an inch in diameter and four inches in length. Two thirds of the length was threaded and fitted with a "butterfly" nut in front of which was a cylindrical plug of guttapercha faced with indiarubber. At the other extremity was a swivelled cross-bar of about an inch in length and so arranged that it could lie in a straight line with the rod. This end Fuller inserted in one of the perforations in the side of the tank. Then, giving the rod half a turn, he allowed the swivel bar to fall into a position at right angles to the rod. It was then impossible to withdraw the latter owing to the cross-piece engaging on the inner side of the tank. The flight-lieutenant's next move was to screw the pliable plug hard against the perforated metal by means of the "butterfly" nut, and by so doing hole No.1 was repaired--the first of six. While Fuller was engaged upon the work of making good defects Kirkwood, his mind still uneasy on the subject of the float, lowered himself over the side. Gaining the upper side of the float he felt along it with his hand. As he did so a wave swept the frail buoyant structure. "By Jove!" he exclaimed. "This is a treat. The water is quite warm." Compared with the intense coldness of the upper air the sea, at this time of the year, was indeed tepid. The contrasted temperature acted like balm to his numbed hands. He revelled in the comfort. While thus engaged the A.P. discerned a large object looming through the darkness--a cylinder nearly a yard in diameter. It was floating with very little of its bulk showing above the surface, and, owing to the comparatively rapid drift of the seaplane, it appeared to be moving steadily through the water and bearing straight down upon the float. For a brief instant Kirkwood remained stock still in his recumbent position, unable to raise a finger or utter a cry. The object was a floating mine. He could discern the horns with remarkable clearness, for the thing seemed surrounded by an aura of phosphorescent light. One blow from the underside of the float upon those delicately adjusted projections with which the mine simply bristled would result in utter annihilation. Kirkwood's mind was steeled to the dangers of a ten or fifteen thousand feet fall through space; but this, to him, unusual danger literally took the wind out of his sails. Then, like a flash, the reaction set in. The will to cope with sudden perils asserted itself. A plan, unpretentious in all its details, formulated in his active brain.