IT was a time when medical opinion could advocate the use of cold bathing, purges and leeches for everything from fevers to scabs and deliriums.

It was also an era when a leading Scottish medical authority would not think it unusual to receive a letter from a patient who had fallen ill after eating an excess of cucumbers.

All of these subjects arise in the correspondence of Dr William Cullen, one of the 18th century's foremost Scottish medics.

The consultation letters are among the treasures in the Sibbald Library of the Royal College of Physicians of Edinburgh.

For the last four years, researchers from Glasgow University have been creating a publicly accessible online digital edition of the letters and the online archive is being launched today.

Dr David Shuttleton, Reader in Literature and Medical Culture at Glasgow University, who led the project, said: "What makes the resource so valuable is not simply the size of it, but being able to hear the diverse voices from the broad range of people Dr Cullen corresponded with.

"Until now, the sheer physical scale of this archive prevented these important historical artefacts from being studied properly but we believe that this new resource will offer considerable new insights, not only into the history of 18th century medical practice, but also into wider society at that time."

Uniquely, Dr Cullen retained all his letters and responses, which together form a remarkable collection of over 5,000 items dating from the mid-1750s to 1790.

William Cullen (1710-1790) began his career as a medical lecturer and teacher of chemistry at the University of Glasgow.

He rose to international fame as the leading figure in the University of Edinburgh's Medical School. He served as President of the Royal College of Physicians of Edinburgh, and was appointed the King's Physician in Scotland.

He became the most influential medical lecturer of his generation, attracting thousands of students to the Edinburgh Medical School. As the pre-eminent Scottish medical figure of his day, his opinion was in high demand and people wrote to him from around the world requesting his advice on treatments.

The correspondence covers a wide range of social classes and geographical locations.

One Scottish plantation owner contacted Dr Cullen from Charleston asking how to cure an American slave's epilepsy. There are enquiries, too, about a Russian Princess with gout. Famous patients include the dying Samuel Johnson, whose biographer, James Boswell, wrote to Dr Cullen for advice.

Until today Dr Cullen's papers could only be accessed by visiting the Sibbald Library. The launch of the dedicated interactive web edition will widen access and provide a resource for academics, practitioners and students.

Prof Derek Bell, President of the Royal College of Physicians of Edinburgh, added: "We hope Cullen's letters will reach a new and much wider audience nationally and internationally."