10 A MOUSETRAP IN THE SEVENTEENTH CENTURY.
The invention of the mousetrap does not date from our days; as soon as societies, in forming, had invented any kind of police, that police invented mousetraps.
As perhaps our readers are not familiar with the slang of the Rue de Jerusalem, and as it is fifteen years since we applied this word for the first time to this thing, allow us to explain to them what is a mousetrap.
When in a house, of whatever kind it may be, an individual suspected of any crime is arrested, the arrest is held secret.

Four or five men are placed in ambuscade in the first room.

The door is opened to all who knock.

It is closed after them, and they are arrested; so that at the end of two or three days they have in their power almost all the HABITUES of the establishment.

And that is a mousetrap.
The apartment of M.Bonacieux, then, became a mousetrap; and whoever appeared there was taken and interrogated by the cardinal's people.