I was kneeling and Stackhurst standing by the body when a shadow fell across us, and we found that Ian Murdoch was by our side. Murdoch was the mathematical coach at the establishment, a tall, dark, thin man, so taciturn and aloof that none can be said to have been his friend. He seemed to live in some high abstract region of surds and conic sections, with little to connect him with ordinary life. He was looked upon as an oddity by the students, and would have been their butt, but there was some strange outlandish blood in the man, which showed itself not only in his coal-black eyes and swarthy face but also in occasional outbreaks of temper, which could only be described as ferocious. On one occasion, being plagued by a little dog belonging to McPherson, he had caught the creature up and hurled it through the plate-glass window, an action for which Stackhurst would certainly have given him his dismissal had he not been a very valuable teacher. Such was the strange complex man who now appeared beside us. He seemed to be honestly shocked at the sight before him, though the incident of the dog may show that there was no great sympathy between the dead man and himself.