Belling the Rat

We know about putting a bell on a cats neck to warn animals of its approach but a RAT?

"A gentleman traveling through Mecklenburgh, some years since, witnessed a singular association of incongruous animals. After dinner, the landlord of the inn placed on the floor a large dish of soup, and gave a loud whistle.

Immediately there came into the room a mastiff, an Angora cat, an old raven, and a remarkably large rat, with a bell about its neck.

They all four went to the dish, and without disturbing each other, fed together; after which the dog, cat and the rat, lay before the fire, while the raven hopped about the room.

The landlord, after accounting for the familiarity of these animals, informed his guest that the rat was the most useful of the four; for the noise he made had completely freed his house from the rats and mice with which it was before infested."