The String of Pearls (1850), p. 190

"Secure it."
"All's right."
Crotchet took a curious little iron instrument from his pocket, and secured it into the wall by the side of the door. It did not take him more than a moment to do so, and then, fully satisfied of the efficacy of his work, he said—
"Let 'em get over that if they can."
While he was so occupied, Sir Richard Blunt himself had opened the window, and fastened it open securely.
"Now, Crotchet," he said, "look to your pistols."
"All's right, sir."
The magistrate carefully examined the priming of his own arms, and seeing that all was right, he at once emerged from the attic through the window on to the parapet of the house. He might have crept along the gutter just within the parapet, but the gutter aforesaid was not exactly in the most salubrious condition. Indeed, from its filthy state, one might have fancied it to be peculiarly under the direction of the city commissioners of sewers. Crotchet followed Sir Richard closely, and in a moment or two they had traversed a sufficient portion of the parapet to find themselves at the attic window of Todd's house. It
would have been next thing to a miracle if they had been seen in their progress, for the roof was very dark coloured, and the night had fairly enough set in, so that if any one had by chance looked up from the street below, they would scarcely have discovered that there was anybody creeping along the parapet.
Now there was a slight creaking noise for about half a minute, and then the window of Sweeney Tood's attic swung open.
"Come on," said Sir Richard, and he softly alighted in the apartment. Crotchet followed him, and then the magistrate carefully closed the window again, and left it in such a way, that a touch from within would open it. Then they were in profound darkness, and as it was no part of the policy of Sir
Richard Blunt to run any unnecessary risks, he did not move one inch from the place upon which he stood until he had lighted a small hand lantern, which had a powerful reflector and a tin shade, which in a moment could be passed over the glass, so as to hide the light upon an emergency.
"Now, Crotchet," he said, " we shall see where we are."
"Reether, said Crotchet.
By holding the light some height up, they were able to command a good view of the attic. It was a miserable looking room: the walls were in a state of premature decay, and in several places lumps of mortar had fallen from the ceiling, making a litter of broken plaster upon the floor. It was entirely destitute of furniture, with the exception of an old stump bedstead, upon which there lay what looked like a quantity of old clothes.
"Safe enough," said Sir Richard.
"Stop!" said Crotchet.
"What's the matter?"
"There's something odd on the floor here. Don't you see as the dust has got into a crevice as is bigger nor all the other crevices, and goes right along this ways and then along that ways? Don't you move, sir, I'll be down upon it in a minute."
Mr. Crotchet laid himself down flat upon the floor, and then crept on until he came to that part of the flooring which had excited his suspicions. As soon as he pressed upon it with both his hands it gave way under them plainly, by the elevation of the other end of the three boards of which this trap was composed, proclaiming that it was a moveable portion of the floor, revolving or turning upon one of the joists as a centre."
"Oh dear, how clever!" said Crotchet. "If Mr. Todd goes on a cutting away his joists in this here way he'll bring his blessed old house down with a run some day. How nice and handy, now, if any one was to step upon here—they'd go down into the room below, and perhaps break their blessed legs as they went."