The smoking of opium as in this Chinese opium pipe is one of humanity's longest traditions Credit: Science Museum/Science & Society Picture Library

Heroin is a chemical derivative of morphine, called diacetyl morphine. At the beginning of the twentieth century the new synthetic drugs such as cocaine and heroin were freely available, although their use was progressively controlled by law.  Experiments with mind-altering drugs became popular among intellectuals such as Aldous Huxley in the 1920s.

These Bronze Age 'base ring' juglets were used to transport opium Credit:Science Museum/Science & Society Picture Library

Burgeoning youth cultures of in second half of the 20th century popularised the use of mind-altering drugs. For some the experiments have been fun and temporary, for others they have led to addiction, poverty and crime. In the 1980s addiction to hard drugs such as both cocaine and heroin became much more common across the western world. It is estimated that a high proportion of all prisoners have been trying to make money to support a habit.  Studies of addiction which had begun with alcohol were broadened to include these new threats to public health. Yet even with better laboratory understanding, the social significance and means of controlling drug use on the street are still elusive.