They rose to a height of five hundred feet above the sea-level, and, at this elevation, found themselves entirely free of the fog. So far this was well, but the dense masses of heavy grey snow-laden cloud which obscured the heavens above them, and the threatening aspect of the sky to windward, told them that their holiday weather was, at all events for the present, gone, and that they were about to experience the terrors of a polar gale. The temperature fell with astounding rapidity; and they were compelled to beat a rapid retreat to their state-rooms, there to don additional garments. This done, they sallied out on deck, to find that during the short period of their retirement a heavy snow-storm had set in, the air being so full of the great white blinding flakes that, standing abreast the pilot-house, it was impossible to see either end of the ship. Floating in the air as they were it was, of course, impossible for them to estimate the strength of the gale, the only apparent movement of the atmosphere being that due to their own passage through it. Though heading to the northward, with the engines making a sufficient number of revolutions per minute to propel them through still air at the rate of thirty miles per hour, it was quite on the cards that the adverse wind might be travelling at a higher speed than this, in which event they would actually be driving more or less rapidly astern, notwithstanding their apparent forward motion. It thus became necessary to post a look-out at each end of the ship, in order to avoid all possibility of collision with some towering iceberg, unless they chose to rise high enough in the air to be clear of all danger; and this they were reluctant to do, as they wished to experience, for at least once in their lives, all the terrors of a polar gale. The baronet accordingly volunteered to look out forward and the colonel to do the same aft, and they hastened at once to their respective stations, Mildmay and the professor superintending meanwhile the engine levers and other appliances controlling the motion of the ship. It was well for them that these precautions were so promptly taken, for the colonel had scarcely reached his post when, through the thick whirling snow which scurried past him, he descried a huge white ghostly mass looming vaguely up in the semi-darkness directly astern, and before he well had time to make up his mind that he actually saw something, the top of a gigantic berg revealed itself close at hand, and his prompt warning cry was only raised in barely sufficient time to prevent the _Flying Fish_ driving stern foremost into it, when the loss of her propeller must inevitably have resulted. Mildmay, however, whose quick ear first caught the sound, promptly sent the engines at full speed ahead, and the danger was averted.