I'm writing a short story that happens in a prison during the French Revolution and I imagine the prison cell to have a toilet that is basically just a hole in the floor.
The thing is I don't know what you call it in English. It doesn't help that I also don't know an exact word for it in my native language. I need a word to refer to the hole itself.
An example sentence for my problem could be:
They tied the other end of the rope on one of the bars of the BLANK.
BLANK being the hole where the prisoner do their necessities.
While trying to translate it I found the words ditch and fosse. But I'm afraid that I'd be misunderstood if I used those words, so I'd be thankful if someone could confirm these for me, or inform me of a new word.