Slopping out is the manual emptying of human waste when prison cells are unlocked in the morning. Inmates without a flush toilet in the cell have to use other means (formerly a chamber pot, then a bucket, now often a chemical toilet) while locked in during the night. The reason that some cells do not have toilets is that they date from the Victorian era and were therefore not designed with plumbing. As a result, there is no space in which to put a toilet, together with the expense and difficulty of installing the necessary pipes.