"I didn't do badly," replied Colin. "I went to Shadwell, saw my friends, had a forty-mile run in the car, and finished up with a dinner and a theatre." The old man nodded grimly. "It sounds rather an exhausting form of recreation. I should imagine that after all that you must be quite ready for your bed." "Oh, I'm not tired," said Colin, "not in the slightest. If you've got anything on hand I should like to come in and make myself useful." "You'll do nothing of the sort," returned the Professor. "You will help yourself to a whisky and soda, and then you will go straight upstairs to your room." Colin hesitated. "And how about you, sir? Surely you've done enough work for to-day?" "I shall be following you shortly," was the answer. "I am only waiting to see the result of a small experiment." He nodded a curt good-night, and, stepping back again into the laboratory, closed the door behind him. Dismissed in this unceremonious fashion, Colin made his way into the dining room, where he found a plate of sandwiches and a siphon set out ready for him on a tray. It was unthinkable that such an idea could have occurred to the unaided intelligence of Mrs. Ramsay, and, rather surprised at the Professor's consideration, he proceeded to mix a drink, which he carried with him up the staircase. His room was situated on the first floor--a large, comfortable apartment looking out toward the back. It had been fitted up since his arrival with a gas stove, and, having lighted this and placed his tumbler upon the dressing table, he began in a leisurely fashion to get ready for bed. The chief subject that occupied his thoughts was the revelation which Nancy had made to him at dinner. What on earth had induced Major Fenton to concoct that ridiculous story about a scandal at St. Christopher's Hospital? That it was an invention of his own Colin felt certain, and no man would take the responsibility of fathering such a lie unless he had some particularly strong object in view. Could he have fallen in love with Nancy himself? If that were the case it would certainly supply a possible motive. Passion has a queer effect upon some characters, and the mere thought of her making friends with any one else might have filled him with such furious resentment that he had clutched at the first conceivable chance of breaking off their acquaintance.