It had been about two o'clock when the chase started, but already those taking part in it were miles upon miles distant from London, since the aeroplanes were flying at the rate of between fifty and sixty miles an hour. Harrow, St. Albans, Luton, Bedford and Northampton had long since dropped behind, and Queen Beelzebub, swerving to the left, was making for Rugby, so as to get into the straight line for Hillshire, and particularly for Thawley. Passing over the famous school-town the pace slackened somewhat, and Dan managed to secure the advantage of a few miles. But when her machine lifted Birmingham, she increased her speed, a fact which made Dan curse. He had been under the impression that she was running short of oil and petroleum, but apparently this was not the case. She had simply reduced her speed so as to nurse her resources, since she could take this bold step because of the start she had gained at the outset. Halliday grudgingly confessed to himself that the woman, knew her business, as she wasted no time. Her machine neither rose nor fell, nor deviated to right or left overmuch, and all she did was to hold to a straight line at a moderate height above the earth, humoring her engine, and straining as little as might be the wings, spars, bolts, and such-like gear of the biplane. Vincent had taught her admirably, and Dan no longer undervalued her as an antagonist. She was dexterous, bold, resourceful, and venturesome. His admiration, now freely given, was mixed with pity that so clever a human being should debase her gifts to harry mankind. Such qualities as she possessed made her more dangerous, as she was an intellectual animal, slaying with taught skill rather than with instinctive cunning. As the afternoon drew on, and the chase still continued, the night began to shut down. Gliding over Derby the town was veiled in the gray mists of swiftly-falling dusk, and when Nottingham came in sight it was distinguished by a thousand glittering pin-points of light, the usual nightly illumination. Matlock, and Mansfield, Holdbrook and Wayleigh, gleamed beneath like jewelled crowns, and when the stars began to appear the aeroplanes were flying between two firmaments, radiant with multi-colored orbs of light.