one of the great front windows. It was fast.
Then Lucifer once again inspired that unhappy man with cunning beyond his own. He whipped out a pocket-knife, opened the thin blade, inserted it in the crack of the sash and began to tamper, yes, to tamper, with the catch. He felt it giving, as he pushed gently and with infinite care lest any sound should betray him, when his heart suddenly stopped beating, and his blood ran dead cold, at the sound of a voice just behind him delivering this summons—
"What yer at?"
He dropped the knife and leapt round. A sturdy fellow, short and thick-set, clothed in old bargee trousers and a pea-jacket, and with that face of labour which the police call "villainous" in their reports, was watching him unmoved.
"What yer at?" repeated the badly-shaven lips.
"I—I was making an experiment," said Professor Higginson at random.
"Yer was," said the thick-set man, and spat. "And now yer 'll cut."
Professor Higginson was dignified.
"My good man," he said
