Progress in the Mid-19th Century: Nightingale, Chadwick, Snow and Simpson » Cholera and John Snow's Broad Street Pump

The cholera threat

Cholera is a deadly disease. It causes violent vomiting and diarrhoea, so the body loses water very fast. A healthy person could fall ill in the morning and be dead by the evening. In the mid-19th century nobody had a cure.

Cholera first reached Britain in 1831 and struck again in 1848-49 and 1854. Each time it was an epidemic, and in each one tens of thousands of people died. It was worst in crowded towns with dirty water and no sewers, the same places described by Edwin Chadwick, a reformer who reported on the bad living conditions in towns. In 1848 the fear of cholera was one reason Parliament passed the Public Health Act, the law that allowed towns to set up boards of health. Remember that most people still believed in miasma, so they blamed the smell of rotting rubbish and waste.

Key terms:

• Cholera: a deadly disease that causes severe vomiting and diarrhoea.
• Epidemic: a disease that spreads quickly and affects many people at the same time.
• Contaminated: made dirty or poisonous by something harmful, such as sewage in drinking water.
• Theory: an idea that tries to explain something, but may not yet be proved.

John Snow's theory

John Snow was a London doctor. He was already famous for giving chloroform to patients (see the lesson on Dangers in Surgery and Simpson's Chloroform). Snow studied cholera closely and thought about its symptoms. They affected the stomach and bowels, not the lungs. If the cause were bad air that people breathed in, he reasoned, the lungs would be hit first. So in 1849 he published his theory: cholera was caused by something people swallowed, and it spread in water that had been contaminated by the waste of cholera victims.

In 1849 this was only a theory. Snow could not prove it, and he could not say what the something in the water was, because nobody had yet identified the cause of cholera.

The Broad Street pump, 1854

In late August 1854 a terrible outbreak of cholera began in Soho, a crowded district of London. More than 500 people living close to the pump in Broad Street died within ten days. Snow lived nearby, and he saw a chance to test his theory. He did three things:

The deaths fell soon after. A local church minister, Henry Whitehead, had at first doubted Snow. He then helped him, and found that the first victim was a baby girl whose house was beside the pump. Her waste had gone into a cesspit that was leaking close to the well. This fitted Snow's theory exactly.

Why Snow's findings were slow to be accepted

Snow's evidence was good, but most doctors and officials did not accept his theory for many years. There were four main reasons:

Snow died in 1858 and did not live to see his work accepted. Attitudes changed slowly in the following decades, and the germ theory and the discovery of the cholera germ finally proved he was right.

Change and continuity: public health and surgery

By the mid-19th century there had been important changes, but the picture was mixed. The boxes show what changed and what stayed the same.

In both cases people could now do more, but they still did not understand the true causes of disease. That is why progress was limited.

Exam-style question

Explain TWO ways in which the ideas of John Snow about cholera were different from those of Edwin Chadwick. (Chadwick believed that disease was caused by the smells from filth, and collected figures from towns across the country to support the 'sanitary idea'.) [6 marks]