Upstairs in their bedroom, with the gas turned on, it was easy enough to feel courageous. Their spirits rose indeed at the prospect of such an adventure. Nurse Warner, who came into the room a little later, looked round at the four beds, turned out the gas, and departed without a suspicion. She had not been gone five minutes when a surreptitious dressing took place, and four figures in dark coats stole down the stairs. Though the building of the College might be absolutely modern, the garden was a relic of mediaeval days. It had formerly belonged to the nunnery of St. Mary's, and had adjoined the Abbey. Parts of the crumbling old wall were still left, and a flagged path led from a sun-dial to some ruins. In the day-time it was a cheerful place, and a blaze of color. The girls had never before seen it in its night aspect. On this May evening it had a quiet beauty that was most impressive. The full moon shone on the great dark pile of the Abbey towers and the beech avenue beyond. There was just light enough in the garden to distinguish bushes as heavy masses, and to trace the paths from the grass. The air was sweet with the scent of flowers. It is amazing how different conditions can alter a scene: at noon, with the hum from the busy streets, it was commonplace enough; by moonlight it became a mystic bower of enchantment. The girls walked along very quietly, treading on the grass so as to make no noise. A slight mist was rising from the ground near the Abbey; in the rays of the moon it resembled a lake. Everything, indeed, was altered. The outline of the sumach bush was like a crouching tiger; the laburnum tassels waved like skeleton fingers. It seemed a witching, unreal world. Four rather scared girls crept along, clasping hands for moral support. Each secretly would have been relieved to abandon the quest, but did not like to be the first to turn tail. They had determined to walk from the sun-dial to the Abbey wall and back again. So far the garden, though mysterious, showed no signs of anything supernatural. They began to pluck up courage, and even to talk to one another in low whispers. At the ruins they turned and looked back towards the sun-dial. The moonlight streamed along the flagged path, and shimmered on the clumps of early yellow lilies. What was that, stealing from under the shelter of the hawthorn tree? The girls gasped and almost stopped breathing. [Illustration: A TALL FIGURE, CLOTHED IN SOME WHITE GARMENT, WAS GLIDING TOWARDS THEM.]