She immediately struck the chestnut--the mare sprang forward and cantered down the lane. Quite beside himself, half with annoyance with her, half with himself, he ran to the grey, mounted, and tried to follow. But the horse was lame. He did his best, limped, stumbled, recovered himself, and shambled after painfully. When Geoffrey reached the edge of the wood, Margaret, a long distance ahead, was riding out upon the Downs--horse and horsewoman a dark figure, indistinct in the gloaming. Fearful of losing her, he called on the grey; but she glided away from him swiftly over the darkening plain and up the opposite hill. For a moment he saw her clear against the sky-line, then she was over the ridge and gone. He thrashed the grey, and forced him rather than rode him up the hill, but there the long-suffering animal stayed his wretched shamble and walked. Wild with anger, Geoffrey dismounted, ran to the edge of the hill, and looked for Margaret. Deep in the wide hollow lay a white mist, covering all things with its cloak. Beyond was a black mass, with undulating ridge against the sky. "The chestnut _must_ walk up that," he thought; and, without a moment's pause, dropped his whip, and raced down the slope headlong. What he should say or do if he overtook her he did not stay to think; but overtake her he would. His long stride carried him quickly to the bottom. He imagined he should find a thick fog there as it had looked from above; but now that he was in it there was nothing more than an impalpable mist, through which he could see for some distance. But upwards the mist thickened, and the hill above was hidden now. He listened--not a sound; then rushed across the level, and threw himself against the next ascent. Panting, he reached the summit; it was but a narrow ridge, and over it another coombe. Instead of a sea of mist here, one long streak, like a cloud, hung midway. No horse visible. Again he dashed forward, and passed through the stratum of mist-cloud as he went down, and the second time as he climbed the opposite rise--more slowly, for these Downs pull hard against the strongest chest. Then there was a gradually rising plateau--dusky, dotted with ghostly hawthorn bushes, but nothing moving that his straining eyes could discern. But as he stood, and his labouring heart beat loudly, there came the faint sound of iron-shod hoofs that clicked upon stray flints, far away to the right. Like an arrow he rushed there--unthinking, and therefore baffled. For instead of crossing the steep ridges, she had ridden round on the slope; and he, running on the chord of the arc, had not only caught her up, but got some distance in front. If he had remained where he was, she would have passed close by him. But running thus to the right in his wild haste, he lost great part of his advantage. Suddenly he stopped short, and saw in the dim light a shadowy figure stretching swiftly into the mist.