With this consoling reflection Colin donned his pyjamas, and, turning out the fire, clambered into bed. He was just in that pleasantly drowsy stage when one feels half reluctant to fall asleep, and, lying there with the light on, he allowed his thoughts to drift back contentedly over the various details of his two meetings with Nancy.
It was an agreeable occupation, and the longer he indulged in it the more he began to realize what a very necessary part of his life she had already become. A kind of instinctive friendship seemed to have sprung up between them at their first encounter, and, although he had been unable to see her again until to-day, the interval had certainly not succeeded in making the faintest difference.
She was a girl in a thousand, there was no doubt about that! Mark evidently thought so, and, since he compared all women with Mary, his standard was about as high as any one could reasonably demand. How enchantingly pretty she had looked as they had sat opposite to each other at dinner. He had only to shut his eyes and——
Hullo! What the devil was that?
The sound had come from somewhere down below—a queer, half-deadened noise, like the distant crash of breaking glass.
In a second Colin was out of bed and had flung open the door. The lights were still burning exactly as he had left them, and, striding to the banisters, he peered over into the hall. Nothing seemed to be stirring; except for the steady ticking of the grandfather clock the whole house was as silent as a tomb.
With a momentary feeling of relief he moved toward the staircase. It was probably only some small accident; the Professor had most likely dropped a tumbler or broken a retort, and in the stillness of the night the noise had been naturally exaggerated. All the same, it would be just as well to have a look round.
Running lightly down in his bare feet, he crossed the hall and knocked at the laboratory door.
"It's I—Gray," he called out. "Anything wrong, sir?"
As he spoke he turned the handle, and the next moment he found himself standing in the open doorway, staring blankly in front of him.