EMITTING gasping croaks, the chap behind me slid down the railings of Blythswood Square, eventually squirming on the rain-soaked pavement clutching his stomach.

"Arsenic poisoning!" shouted Mr Dark, dressed in a Victorian frock coat, making a quick, yet perceptive, diagnosis. Bob the dog, a bemused collie, merely barked at the strangeness of it all as a dozen onlookers mutely watched the tableau. Although what can you really categorise as strange in Glasgow on a Friday night?

Those of you astute scholars of Victorian crime will have put Blythswood Square and arsenic poisoning together and come up with the name Madeleine Smith. Yes Madeleine, daughter of an eminent Glasgow architect, who had unwisely written some 300 letters to her lover Emile L'Angelier and was a tad annoyed when he refused to return them when she was about to marry an older but richer man. Smith stood trial for murder after L'Angelier died of arsenic poisoning soon after Smith had bought large doses of the poison either to shorten the lives of rats or as a skin treatment, depending on which tale she told. The case was found not proven as the jury couldn't stomach sending a pert young girl to the gallows for doing away with an interfering foreigner.

Oscar Slater, a German Jew, was another foreigner who had arrived in Glasgow, only in his case he was accused of a murder of someone he claimed he had never met. So sure was Slater of the Scottish justice system that he sailed back from New York to clear his name. Poor choice, as he was found guilty even although the only evidence was the tenuous identification of him near the scene by witnesses who changed their story frequently, and only hardened up their identification of Slater once it became clear that they would benefit from a substantial reward.

Thankfully the authorities couldn't bring themselves to hang Slater on such a flimsy case and he was sent to Peterhead Jail for life instead. He was freed 19 years later after numerous campaigns to save him. He then lived out his life peacefully in Ayr, which even cynics would accept is marginally better than hard labour in Peterhead.

Both Smith and Slater, over a century later, are still remembered in an evening walking tour in Glasgow entitled One Square Mile of Murder, centred on Blythswood Square, the home of Smith's family. It is organised by the Spirit of Glasgow company, which also creates murder mystery dinner parties featuring Smith's case for those who prefer to hear about murders on a full stomach.

The night I went on the tour a couple even brought their collie dog, who added his own sound effects when one of the actors screamed or shouted. I'm sure there were lots of dogs in Victorian Glasgow, so well done Bob for adding verisimilitude. The actor in charge, Mr Dark, possibly not his real name, told me that most of those taking part in the 50-minute tour are not visitors but Glaswegians keen to know a little about their city's past.

Curious what tours a city offers? In New York there are Sex and the City tours and Sopranos tours, concentrating on the cafes, bars and landmarks featuring in the television series. In Glasgow the equivalent would be a Taggart tour, but I can't recall any memorable scenes in Taggart other than dingy pubs and a back shop where black puddings were made, so not quite the glamour of Sex and the City.

Dublin has of course the civil war to add spice to its walking tours, including the bullet holes still extant on the GPO where the rebels set up their headquarters. I'm no historian, but it is hard to imagine as the bullets whizzed overhead that the rebels sheltering behind pillars were shouting at each other: "Should we still go ahead with this? The English Government may not agree on a currency union if we succeed!" But I digress.

So Glasgow, glibly regarded as the murder capital of Europe if you twist the statistics in certain ways, has a murder tour. But at least it is about the intrigue of Victorian and Edwardian times rather than the prosaic deaths among the squalid drug dealings of the city today. But who knows? Perhaps a century later tourists on their hoverboards will be visiting where Arthur "Fat Boy" Thompson Jr met his death or the scene where the bodies of drug enforcers Bobby Glover and Joe "Bananas" Hanlon were discovered on the route of Fat Boy's funeral cortege.

No, far better to muse over Madeleine Smith's case and wonder if, just maybe, her arsenic purchases were a coincidence. However, as Donald Findlay QC said in the introduction to Jack House's splendid book on the cases, also entitled Square Mile of Murder: "Madeleine's defence counsel, the Dean of the Faculty of Advocates, reputedly said after his client's acquital, 'She is a bonny lass, but I wouldn't take supper with her.'"

Personally speaking, I'm often accused of getting away with murder when I write The Herald Diary.

At least I can say I'm not the first Smith in Glasgow to have done so.