York's memorial to 'the greatest doctor of all time'

It looks for all the world like a Victorian water pump, minus its pump handle (which is lying on the ground nearby). And that is, in fact, precisely what it is.

Nearby is a small blue plaque set neatly into some paving. "John Snow (1813-1858)," it reads. "Pioneer of public health and anaesthesia. Proved that cholera is water-borne."

So who was this mysterious John Snow? And why on earth has someone planted a Victorian water pump in North Street Gardens in his memory?

Snow was born in North Street on March 15, 1813 - 204 years ago. The street was then one of the poorest parts of York, and Snow came from the humblest of beginnings: his father, William, was a labourer in a nearby coalyard.

Yet despite this, Snow rose to become one of the most famous doctors of his age. He was a pioneer in the field of anaesthetics - and in fact was so highly regarded that he was called in to help Queen Victoria during two of her pregnancies, administering chloroform to the queen during the birth of her children Prince Leopold, in 1853, and Princess Beatrice, in 1857.

Quite something for the son of a coal-yard worker from York. But it isn't for being Queen Victoria's anaesthetist that he's best known today.

'Greatest physician of all time': John Snow

In 2003, a poll of British doctors ranked John Snow as the greatest physician of all time. You don't get that kind of recognition for administering painkillers - not even to a queen.

No. John Snow's real contribution was much more significant. He worked out how cholera, one of the most feared diseases of Victorian times, was spread. His findings were resisted by medical opinion of the time. But it was a discovery of huge significance - because once you know how a disease is spread, you hopefully know how to stop it spreading.

For his work on cholera, Snow is recognised today as one of the founding fathers of epidemiology - the branch of medicine dealing with the spread of disease and how to control it. It is a science that has saved countless lives the world over. And Snow - the little boy who grew up in the slums of North Street - was the man who started it all.

He did it by tracing the origin of an outbreak of cholera in Soho, London, in 1854. As well as working as an anaesthetist, Snow also ran his own London medical practice. He had long been interested in the way cholera spread - and in 1849, had noticed that fatality rates from the disease were particularly high in London in areas supplied by two water companies: the Lambeth, and the Southwark and Vauxhall. When the Lambeth moved its waterworks further away from the London sewage, mortality rates dramatically dropped, Snow noticed.

Blue plaque next to the John Snow memorial in York

Medical opinion at the time believed that cholera was transmitted through the air. Snow, however, was convinced that it was spread by water. If it was spread by air, he pointed out, the symptoms should appear first in the lungs - whereas in fact they appeared in the stomach and bowel.

In 1854, an outbreak of cholera struck in Broad Street. Within the space of ten days, 500 people died.

Determined to trace the source of the outbreak, Snow applied a scientific approach. He obtained a list of the people who had died, and plotted a map showing where they all lived. It showed that most of the deaths had occurred in the neighbourhood of a public water pump in Broad Street.

Snow persuaded the local board of guardians that the pump handle should be removed (as it has been in that memorial in York) so that no-one could draw water from the pump.

The new John Snow memorial in York: a Victorian water pump with the pump handle removed...

It was a decision that has since been credited with ending the outbreak. In fact, the outbreak may already have been coming to an end. Nevertheless, a parish cholera enquiry committee was set up, and the source of the outbreak was officially identified - the Broad Street pump. Snow had been right.

The medical world still refused to accept that infected water was the source of Cholera. It was only in the 20th century that Snow's work became fully appreciated. But he had set out the principles of epidemiology - the scientific approach to understanding how disease spreads. And for that, he fully deserves to be known as one of the greatest physicians of all time.

The water pump memorial in North Street, close to where Snow was born and brought up, is the perfect memorial, therefore.

It is the result of a collaboration between York Civic Trust, York Medical Society and the University of York, with support from the City of York Council, York Hospital and Yorkshire Water.

And it was officially unveiled on March 15 - the 204th anniversary of Snow's birth - by his great-great-nephew Geoff Snow. Geoff's daughter-in-law, Dr Stephanie Snow, a historian who has studied Snow's life, was also present at the unveiling.

Prof Hilary Graham of the University of York's Department of Health Sciences said the unveiling of the memorial meant that at last, one of York's great unsung heroes had a monument worthy of him.

It is a monument that should serve as an inspiration to a new generation of York people, said David Fraser, chief executive of the York Civic Trust.

York Civic Trust chief executive David Fraser at the unveiling of the John Snow memorial

"John Snow is one of the most important people our city has ever produced - his work has had profound implications on a global scale," he said.

"I do hope that when young people see his memorial as they pass by the gardens in North Street... they will see him as an inspiration. It really is possible for a person of ordinary background to change the world for the better."

FROM HUMBLE BEGINNINGS TO VICTORIA'S ANAESTHETIST

John Snow's father William must surely take some of the credit for his son's brilliant career.

When John was born in 1813, William was a humble labourer in a nearby coalyard. But William was a man clearly determined to better himself and his children.

By 1819, he had changed his job, becoming the driver of a horse-drawn cab. With the income from that, he was able to buy a house in Queen Street - and then four more houses and a yard in the same street, which he rented out to boost the family income.

By 1841, the census shows that he was doing so well he had moved out of York altogether to become a farmer in Rawcliffe, according to research by the York Civic Trust and by Dr Stephanie Snow, the daughter-in-law of John Snow's great-great nephew, Geoff.

William and his wife Frances had nine children in all. In an age of high infant mortality, they lost only one of their children - George, the youngest, who died at the age of 18 months. But the Snows were clearly determined that the rest of their children should get a decent education. Two became teachers, one a clergyman, one a colliery manager, and one ran a temperance hotel in York.

And one, of course, became a doctor.

John Snow

In 1827, when he was 14, John was apprenticed to William Hardcastle, a Newcastle surgeon-apothecary who had been born in York and seems to have known the Snows. John attended classes at the Newcastle School of Medicine, became an assistant medical practitioner then, in 1836, at the age of 23, scraped together enough money to enrol at the Great Windmill School of Medicine in London.

He became a member of the Royal College of Surgeons and then of the Royal College of Physicians.

His work on anaesthetics - he developed an inhaler that was able to control the amount of ether or chloroform that was administered - led to him assisting Queen Victoria at the birth of two of her children.

But it was his work on cholera that has ensured his lasting fame.

Snow died in 1858, aged just 45, after suffering a stroke. He never married. But his name will be revered as long as there are doctors to celebrate it.