For the Pretender had sprung up and was dragging on his boots. He was finding it impossible to pretend any longer.
John watched him anxiously, all uncomprehending.
"Better let me take your temperature, Mac. Diphtheria's fairly booming in your year. Packard has it now."
"Nonsense! I'm all right. You meds. are always on the trail of death and disease."
"I thought you said you were going to plug to-night."
Charles Stuart was savagely dragging on his overcoat. "Well, I'm not, I'm going out."
"You haven't a pain or an ache anywhere, have you?"
The patient might have answered truthfully that he was conscious only of one great ache through his whole being, but instead he answered shortly: "Pain? Your granny! No, of course not!"
The door slammed soundingly behind him, and John sat gazing at it until the house shook with another tremendous bang, this time from the street door.
"Well, I'll be——" said the young man, and then paused, feeling how utterly hopeless it was to find a word expressive of his feelings. In all the years of their life-long comradeship he had never known Charles Stuart to behave in such a manner. "He's gone batty!" he said at last to the closed door, and then slowly and meditatively he returned to his books. "He's fixing for dip. all right," he added; "I'll have Bags in to overhaul him when he comes back." Then, with the satisfaction of a medical student who has correctly diagnosed and prescribed for a case, he settled himself comfortably in the easy-chair and went to work.