At the time it was one of the biggest ever crowds gathered in one place in Glasgow.

More than 100,000 people waiting the arrival of probably the most famous or infamous man in Scotland.

However this wasn't a football match or an open air music festival with a big name act.

The man they were waiting to see was a father-of-five who had been convicted of murdering his wife and mother-in-law following a trial that had both shocked and gripped Scotland.

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Glasgow Times:

Edward Pritchard, 40, was about to be hanged in public on Glasgow Green having been sentenced at the High Court in Edinburgh.

However Pritchard was no ordinary double killer - he was a respected city doctor and GP with a successful and thriving practice.

He had not only been accused of a double murder but was alleged to have had a fling with a young 15 year old housemaid from Islay, Mary McLeod, Having got her pregnant, Pritchard then forced Mary to have an abortion which he administered himself.

Ironically the killer doctor wasn't Glaswegian or even Scottish.

Edward Pritchard had been born in the seaside town of Southsea, near Portsmouth to a respected naval family.

He claimed to have studied medicine at King's College Hospital in London and to have graduated from there in 1846.

Pritchard then served in the Royal Navy as an assistant surgeon on Nelson's ship at the Battle of Trafalgar, HMS Victory.

For another four years, he served on various other ships sailing around the world.

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Glasgow Times:

He returned to Portsmouth where he met his future wife, Mary Jane Taylor, the daughter of Michael Taylor a successful silk merchant from Edinburgh.

The couple married in 1851 and he had his five children with her.

Pritchard resigned from the Navy and took a job as a general practitioner near Scarborough in Yorkshire.

Being well travelled he was also the author of several books as well as medical articles in The Lancet.

In 1859, he left under a cloud and in debt, and made the fateful move to Glasgow's Berkeley Street, then one of the most sought after and exclusive residential areas in the city.

Within a few years the finger of suspicion began to be pointed at the doctor over his conduct Pritchard was treated with disdain by his fellow GP's who dismissed his tall tales of travels around the world.

There were even claims that his medical degree was a fake and rumours abounded of affairs with patients and servant girls both in Glasgow and back in Yorkshire.

Once settled in Glasgow Pritchard tried, but failed, to join the city's elite medical societies.

He also made an effort to ingratiate himself in social circles with claims that his brother was the Governor General of Ceylon, and that he was a personal friend of then Italian leader Garibaldi.

He even had a walking cane with the inscription: 'Presented by Gen. Garibaldi to Edward William Pritchard'.

The doctor also had a bizarre habit of walking down the street, handing postcards which contained his own picture to complete strangers.

In May 5 1863, there was a fire at the Pritchards' Berkeley Street house which killed 25 year old servant girl, Elizabeth McGrain.

The fire started in her room but she had made no attempt to escape, suggesting that she was unconscious, drugged, or already dead.

The fire was considered suspicious enough for the Pritchard's insurance company not to pay out, but there were no criminal charges despite a police investigation.

The Glasgow Herald of May 6, 1863 reported:"It is said the poor girl, who has met such an untimely death, was in the habit of reading in bed and the supposition is that after she had fallen asleep the gas-jet which was close to the head of the bed had ignited the bed-hangings and the deceased had been suffocated by smoke,”

In 1864, the Pritchards moved to Sauchiehall Street and the following year Mary Pritchard fell ill in mysterious circumstances.

Glasgow Times:

Her worried mother Jane Taylor then moved through to Glasgow to nurse her daughter.

There, on February 25 1865, Jane also fell ill and died at the age of 70. Mary died a month later on March 18 at the age of 38.

Both women were buried in the family lair at Grange Cemetery in Edinburgh. Grieving Pritchard is even said to have opened his wife's coffin on the day of her funeral to give her one final kiss.

The Procurator Fiscal in Glasgow however had received an anonymous letter claiming that both deaths were suspicious.

The police launched an investigation and Pritchard was arrested at Queen Street Station while returning from his wife's funeral and taken into custody.

The bodies of both women were exhumed and found to contain the deadly poison Antimony Pritchard had been putting the chemical compound into both women's food, drink and medicine.

Following each death he falsely certified the causes of death saying that his mother-in-law had died of a stroke and his wife from gastric fever.

On July, 1865, Dr Edward Pritchard stood trial at the High Court in Edinburgh.

Here was a respected pillar of the community with a shady past who had been having an affair with a young girl and accused of poisoning two women, his wife and mother-in-law.

One paper reported: "No one who saw the intelligent, thoughtful and mild-looking individual seated in the dock on the first morning, could be prepared for anything like the consummate villainy and diabolic cruelty which each day brought to light."

Most of the damning evidence came from servants in the Pritchard household, including young Mary.

They highlighted the links between both murder victim's bouts of illness and food the doctor had served to them.

Pharmacists were interviewed and it was acknowledged that Pritchard could easily have acquired large quantities of Antimony.

Pritchard tried every legal trick in the book to avoid the hangman's noose He even made two of his children give evidence and tell the court how much their father loved their mother.

Tears trickled own his cheeks as they stood in the witness box.

But evidence of his affair with young Mary ripped his credibility to shreds - not to mention the poison in the dead bodies.

The jury took just one hour to find him guilty and Lord Inglis passed the death sentence.

Pritchard was accused of "crying crocodile tears" over the death of his wife, earning him the nickname 'The Human Crocodile'.

He also got another nickname -The Poisoning Philanderer - when his fondness for women - particularly teenage maids - became public.

Following conviction and sentencing, Dr Pritchard insisted he was innocent of killing his mother-in-law and that Mary McLeod had been complicit in the murder of his wife.

Nine days before his execution, he eventually cleared her name and shouldered the entire blame He was hanged for his crimes on July 28, 1865, on the gallows at Jail Square on Glasgow Green facing Nelson's Column.

The crowd cheered and booed Pritchard's arrival din the gallows, wearing a dark suit and polished black shoes.

Normally curtain would be drawn below the scaffold so the prisoner could suffer their last moments in privacy.

But on this occasion, in acknowledgement of his horrific crimes, the spectators were allowed to watch the condemned man's final moments.

A noose was placed around his neck and a white cap placed on his head.

The executioner released the trap and Pritchard dropped to his death.

There were no tears for The Human Crocodile as he suffered the ultimate public humiliation.

Pritchard was buried in the 'Murderers' Graveyard' on the site of the current High Court where the plots were only identified by the initials of the dead.

Pritchard was what we woukd call today a narcissistic sociopath.

A man confident of his innocence and refusing to admit guilt until shortly before he was hanged.

It was never quite clear what Pritchard's motive was for the double murder and how he developed into the double killer that drew 100,000 Glaswegians to his execution.

His mother-in-law had left two thirds of her £2500 estate (worth around £350,000 now) to Mary Jane so greed was probably the most obvious reason as the doctor was reputed to have many debts.

Pritchard's death was also the last public execution in Scotland.

In the wake of a Royal Commission all executions in Great Britain were carried out in prisons from 1868.

Hanging was eventually stopped in Britain in 1965 - one hundreds years after the death of the Human Crocodile.