An instant later a bright stream of light shot forth from the prow of the “Royal Dean,” flooding with its radiance the pursued. Captain Mortimer and the Professor saw that the craft before them was slightly larger than their own, of a dead black color and contained three men. “Ahoy, there!” came a moment later the hail from the pursued. “Who are you? What company do you belong to?” Captain Mortimer rose to his feet. “Halt!” he commanded. At sight of his uniform in the glare of the search-light, there seemed to be a sudden consternation among the pursued. Their air-ship shot upward to greater heights. Instantly the Professor handled his levers and followed. A hurried conference between the pursued seemed to be taking place. Captain Mortimer picked up a repeating rifle from the floor of the air-ship. “Surrender!” he shouted, his voice ringing strong and clear; “surrender, you rebels, in the name of the King!” No attention was given to this summons. The pursued kept steadily on, heading toward the north. “Halt!” again commanded Captain Mortimer, raising his rifle. “Halt, or I fire!” For answer to this, a man appeared in the stern of the pursued bearing before him a bowed shield. From the ease with which he handled it, it was apparently very light but doubtless strong enough to withstand a bullet. There was a steel projection at the base of this shield and, in the light of the flash-light, they saw him drop this projection into a socket. The shield was thus held in place and the occupants of the air-ship protected from any pistol, or rifle fire, from the rear. It was a revelation to the pursuers. The attacking party was not only furnished as an aërial scout, but was furthermore equipped as a species of armored aërial cruiser. The Professor drew his companion’s attention to this fact. “Yes,” answered Captain Mortimer, “and if they were supplied with means of offense, such as repeating rifles, they would be not only an aërial cruiser, but a very effective aërial man-of-war. Do you think there’s any vital part of their craft, so that I could disable them with a bullet?” “Our craft could not be so disabled,” answered the Professor; “neither, so far as I can judge, could theirs be.” “Then we must flank them,” said Captain Mortimer, “and try to bring them to terms in that way.” “Very well,” answered the Professor; “I’ll see what I can do.” He accordingly endeavored to navigate his craft to a position on their left quarter, but the pursued were wary and quickly shifted, keeping the protecting shield between themselves and the pursuers. At last, by clever manœuvering, the Professor had almost succeeded, when up went another shield, effectually protecting a large section of that quarter. “It’s no use,” exclaimed Mortimer, laying down the rifle; “it’s a veritable armored cruiser. No matter what quarter we flank them on, they undoubtedly have enough shields to protect all sides. By heaven! they seem to be drawing away from us.”