Then Simon stood back and watched two thick greenish clouds rolling down towards the street like a couple of ghostly slow-motion waterfalls.
As he stood there, a heavy hand tapped him on the shoulder.
" 'Ere," said a voice behind him, "what's this?"
"Chlorine," said the Saint coolly. "A poisonous gas. I shouldn't go any nearer: it would be unhealthy for you to get under that stream."
"I saw you smash those windows."
"That must have been amusing for you," murmured the Saint, still gazing thoughtfully upwards. "But since they're my own windows, I suppose I'm allowed to smash them."
The policeman stood beside him and followed his gaze upwards.
" 'Ow did that gas get there?"
"It was left there," said the Saint gently, "by an assistant commissioner of Scotland Yard who has a grudge against me. I might have walked right into it, only I happened to look up at the windows, and I remembered leaving them open last time I went out. They were closed before I opened them again with those spanners, and that made me look hard at them. You could See a sort of mistiness on the panes, even in this light."
The constable turned, and suddenly a gleam of recognition came into his eyes. He peered at the Saint more closely, and then he released a blasphemous ejaculation.