Prisons and Houses of Correction (see Gallery Punishment 1450-1750), had survived from earlier centuries almost unchanged. They began to be criticised in the late 18th century on a number of counts. All kinds of people were dumped in them together: men, women, children, lunatics, debtors and those simply awaiting trial. They were often ancient and unhealthy places, with no fresh water, or sewage disposal. What they called "gaol fever", probably typhus, killed many inmates. Prisoners had to pay fees to their gaolers, so better off prisoners could survive quite well, while poor prisoners lived in squalor and rags. Local control and local rules meant that there was no common treatment policy across the country.

Several reformers, notably John Howard, described all these abuses, pointing out that prison was meant to be the punishment itself, not the sickness or death which could result. However, change came only gradually. In 1815 gaolers began to be paid, instead of charging fees. Some new prisons were built to new designs, so that prisoners could be easily guarded, but lived in healthier conditions.

Not until the 1830s, with crime on the increase, did the great debate begin on prisons and how they should be run. As other punishments faded out of use and transportation ended, (See Case Study 1), prison became the normal punishment for most serious offenders. But how should they be run?

• The Separate system. Under this system, based on Cherry Hill Prison in Pennsylvania, USA, prisoners were kept in solitary confinement, in order to think about their life and crimes. It was believed that they would then come face to face with the error of their ways. Living conditions were good, but convicts had nothing to do. Christian ideas of repentance and judgement were emphasised. The Chaplain played an important part in this. At Pentonville, a new prison opened in 1842 under the separate system, several prisoners went mad and three committed suicide.
• The Silent system. Under this system, based on Auburn Prison, New York, USA, prisoners had to work, but in total silence.
• Hard bed, hard board, hard labour. In the last part of the 19th century prisons were made even tougher, under a regime called "hard bed, hard board, hard labour". Hard plank beds replaced hammocks, food was deliberately boring and inmates had to work hard on monotonous, even pointless tasks.

To further bring prisons into line, they were all taken out of local control and put under the government, through the Home Office, in 1877. By this time the usual sentence was one year in solitary confinement, followed by three years hard labour. Even time off for good behaviour was stopped.