“A terrible madness and the use of ardent spirits” was the reason why Dr. Edward Pritchard became a double-murderer – at least, it was the reason he gave out in the death cell. It had always been the doctor’s ambition to become the most talked-about man in Glasgow, and as he walked to the scaffold he could congratulate himself on having achieved it.

He had been convicted, after a five-day hearing in Edinburgh in July 1865, of poisoning his mother-in-law, Mrs. Jane Cowan, 70, and his wife Mary Jane, 38, at their home in Sauchiehall Street, Glasgow. The murders were revealed after an anonymous letter was sent to the authorities.

The exhumations of the two bodies showed that they contained a cocktail of poisons – tartarised antimony, aconite and opium. The family’s physician, Dr. James Patterson, told the court at Pritchard’s trial that in his view Mrs. Pritchard was being slowly poisoned.

One motive stood out – the doctor was having a lustful affair with his 17-year-old maidservant, Mary McLeod. She told the trial that Dr. Pritchard had promised to marry her after his wife’s death.

On her death Mrs. Prichard’s life insurance would present her husband with an annual sum of £2,500. Although this would revert to their children when they reached adulthood, it suggested another motive.

Dr. Pritchard was a celebrated figure in Glasgow, not just as a medical man, but also as writer, poet and speaker. He also stimulated his own popularity in some bizarre ways. An admirer of the Italian revolutionary Garibaldi, he had a walking stick inscribed “To William Pritchard, from his friend General Garibaldi,” and was fond of showing off the spurious “gift” to visitors.

He was hanged in the Jail Square outside Glasgow’s South Prison on Friday, July 28th, 1865, the last person to be hanged in public in the city. Barricades were set in place to try to limit the crowds, but still “a vast concourse of persons witnessed the execution.” Pritchard suffered in death – his shoulders convulsed a dozen times after the trap-doors opened, and he didn’t stop moving until the executioner went beneath the scaffold and straightened his legs.

After the hanging it was suggested that two years earlier, in May 1863, he had murdered a servant girl with whom he was having an affair, after her charred body was found in his burnt-out home.