"Uh-huh. Now let's digress for a second. You," said H.M, abruptly, to Sergeant Davis. The sergeant, who had been twisting his moustache like a villain in a melodrama and looking gloomily at Antrim, seemed a trifle startled; but he brought himself to attention. "You were the feller, weren't you, who sneaked into Hogenauer's garden one night and peeped through the slit in the shutter? That was when you saw the little lights movin' round a thing like a flower pot turned upside down. Hey?"
"Yes, sir."
"As I understand it from the description, there's two windows in that room. Hogenauer usually sat by the left-hand window as you face 'em from outside. But for this little experiment he changed the furniture round and sat by the right-hand window. Was he sittin' by the left-hand window when you looked in?"
"The left-hand window. Yes, sir."
H.M.'s drowsy stare grew glazed again. "Could you see anything besides the lights and what we'll call the flower-pot? For God's sake be careful, son. Think."
Davis studied the idea. "No, sir. Nothing else at all, except possibly what might have been the back of a chair: and not much of that."
"D'jou look through the other window, too?"
"Yes, sir. Same result. There wasn't anything there, of course, but the size of the chinks in the shutter wasn't much different."
H.M. turned back to Antrim, who seemed badly puzzled. "Now that the little digression's over," he pursued almost cheerfully, "we can go back to horses and beans again.
There's this little question of Hogenauer's pet brand of mineral-water. Did you know he drank only that?"