Neither of the two who watched him as he moved was quite clear what he was about, but the sight was exceedingly diverting, and a slow and puzzled smile came into Rouse’s countenance. “It’s Coles he’s after,” whispered Terence, after careful observation. “What’s he going to do?” “Heave a brick at his window, perchance,” said Rouse, hoarse with delight. “He’s got an idea that Coles has some mysterious kind of hold over that kid Carr, and he says the way to find out what it is is to get a hold on Coles. He’s starting by getting a hold on the drain-pipe, you see. I hope he won’t let go. I shouldn’t at all like to see our Henry a mere splash of vermilion on the gravel path. Fancy having to clean up Henry with a spade....” His voice trailed away into silence. Slowly, and with considerable difficulty, Henry laboured up the pipe. Once he paused and seemed to be grunting out a prayer for the strength with which to continue. He looked down dizzily, then up again, and finally, after a battle with his nerves, continued the perilous ascent. At last he came opposite Coles’ window. He reached out a hand like that of some family ghost, clutched the window-ledge, and drew himself up to a moderately secure position. The moment had clearly come for the dénouement. Henry was the master-detective in his element. He pulled his cap furtively over one eye. Then he raised his hand and rapped three times upon the window-pane. There came a sharp silence in the room, and afterwards a sudden scuffle over chairs. Evidently Henry was to be rewarded. Somebody could be heard coming to the window. Henry gritted his teeth. He was going to see inside that room. He was going to get a hold on Coles. He became absolutely tense with expectation. Assuredly Coles would never dare to push him off the pipe. Coles was not prepared to commit a horrid murder. Also his rear was safe from attack. Coles could not kick him. The only possibility was that Coles might run out of the house and throw pebbles. He was going to risk this. He would have seen inside the room anyway. When at last the blind was slowly lifted, those within sustained a terrible shock. Henry had thrust his face against the window so that his nose was flatly upturned, hideous and blue, against the glass. The row of faces that confronted him, the faces of Coles’ cronies, all slowly backed terror-stricken before the alarming apparition, till only the face of Coles was left, livid with fury and flushed with spirits flowing from a teapot. He slowly pushed up the window, then his face came forward telescopically on the end of a long neck until his beak-like nose was almost touching Henry’s cheeks. “You cur,” said Coles, between his clenched teeth. “What—what on earth are you doing here?” Henry quailed. Coles was too terrible for words. Nevertheless he peered over the tops of his spectacles resolutely into the study, and at last, still trying to be brave, he spoke in a deep voice: