Inside a tiny bottle was a dice-sized cube of tissue from the brain of one William Burke, famous, even now, nearly two centuries on, as half of the notorious Scottish serial killing team, Burke and Hare.
For a year in 1827/28 in Edinburgh, the pair murdered 17 poor souls and delivered their sometimes still-warm corpses to the local medical school for dissection, being paid around £10 per body by a respected doctor professor who turned a blind eye to the detail of the deaths.
When their crimes were discovered and the authorities seized them, Hare betrayed his murderous mate and was set free. Burke was hanged before an excited crowd in Edinburgh, publicly dissected and then divided into bits and pieces for distribution and sale as souvenirs.
Hence the brain in the bottle.
For travellers with a dark curiosity, there's maybe only one place in Britain to be - north, in Edinburgh, where there are more bits of Burke to be seen, and that's just the scary start of it. Truth be told, the ancient and beautiful Scottish city is a must-see destination for anyone with a taste for the grim and spooky side of tourism - a macabre mecca, in fact.
The city's famous Old Town has closes, lanes and wynds that tumble and tangle down from the castle. High on its rock, is a kind of grim theme park. It's here, in the midst of the old medical school that an intrepid terror tourist can find the Surgeons Hall Museum, which contains, among its hundreds of grisly exhibits, a cast of beastly Burke's head, the mark of the noose deeply imbedded round his neck. And, next to it, a book made from his skin.
Nearby, in more heroic repose, is a life-size model of Robert Knox, the doctor who bought the bodies and, thanks to his status, suffered no punishment, though his once-shining medical career never quite recovered.
But Burke and Hare are only the beginning of an investigation of the dark side of Edinburgh - though don't be tempted to visit the Burke & Hare Tavern at the top of the Grassmarket. It's a strip joint.
Better to wander the short distance to Greyfriar's Kirkyard, where there's no end to the evidence of Edinburgh's shadowy past. When they buried the dead of Edinburgh here - and you can spot graves dating back to the early 16th century - they seemed to take some grim pleasure in reminding all who gazed upon them of what lies beneath the veil of flesh.
Many of the ancient monuments are decorated with memento mori - skulls and bones carved into the weathered stones, sometimes adorned around busts of the departed.
Approach the castle, pause at the top of the narrow cobbled lane that leads to it and, almost hidden for shame round a corner wall, is a small plaque marking what they call the Witches' Well.
On this spot, across a period of a century or so, perhaps as many as 4000 women of the town were burnt as witches.
The plaque shows two faces - the innocent girl and the evil witch. Both died.
And, if it's a spooky reminder of the old human cruelty you want - and you're prepared to pay nine quid for the experience - head down to the part of old Edinburgh they call the South Bridge and take one of the tours of the city's underworld.
Back in the 1770s, the city fathers decided to raise the town centre and built right on top of the older, lower part of the tumbledown town.
After a few years, the city's vagabonds and street people moved in and called the fetid dark vaults and buried alleys home - until the authorities drove them out and sealed the entrances.
Unsealed now for the tourist trade and even wedding functions, they've found an odd new life. Our guide shone his torch through the bars of the gates on one of the vaults to reveal the meeting place of a local witches' coven, the statue of a golden naked woman rising above an altar.
They're good witches, or Wiccan, the guide said. They rent the space. They had a vault further along but said it was haunted by a malevolent spirit and moved. There was a circle of stones, built by the witches to contain the spirit.
I dared the guide to step in, but he said he'd rather not. I felt the same way.
Wandering back up the heart of the Old Town, with its cobbles and towering tenements, who should we encounter, putting the "open" sign up outside her tarot reading parlour, but the world's most pierced woman.
Well, that's what she said, and by the look of her, she was right. "Nine thousand," she said, reluctantly smiling for the camera. "I'm in the records."
Another grim local legend is marked in the name of a pub in the Old Town, Deacon Brodie's Tavern, with its two signs bearing the two faces of its namesake - the respected businessman Brodie was by day and the criminal he was by night. It's said that a fellow townsman, Robert Louis Stevenson, based his Jekyll and Hyde story on him.
Brodie, a gifted furniture maker, was hanged for his crimes on a scaffold he himself had designed and made for the city just a short time before, which is an interesting way to become legend.
But that sort of thing seems to happen in Edinburgh.
CHECKLIST
Getting there: All three Emirates daily services from Auckland connect through Dubai to Glasgow, with fares starting from $2829 return. Trains connect Glasgow with Edinburgh.
Further information: See burkeandhare.com.
Colin Hogg travelled to Edinburgh at his own expense.
