On 24 June 1902, aged forty-six, he was shot and killed, along with a student, by a mentally disturbed gunman in his own laboratory at Surgeons Hall, Edinburgh.

The Scotsman ran a contemporary view of him the day after his death: "Few men were more widely known in Edinburgh or more affectionately regarded than was Colonel Ivison Macadam.

To scientific men he was known as a clever and highly qualified analytical chemist, an able and interesting lecturer on that subject, and a prominent and useful member of learned societies.

The tragedy of his death was deepened by the fact that it came on the day when he was to command a special representative Volunteer Battalion to take part in the Coronation celebrations.

"[8] Professor W. Ivison Macadam was ahead of his time in the teaching of women and encouraging them to participate in courses and degrees, particularly at Surgeons Hall and the New Veterinary College, Edinburgh, in spite of women being banned from attendance at his or other's university lectures and from taking academic degrees at most universities and colleges in Great Britain (most professors and all-male student classes objected to their participation in the academic professions at the time).

After her voluntary service on the front with the British armed forces in the First World War attending wounded, maimed and lame war horses and the enactment of the Sex Disqualification (Removal) Act 1919 she was finally presented with her diploma by the President of the Royal College of Veterinary Surgeons in London on 21 December 1922 thus officially becoming the first woman Veterinary Surgeon in Great Britain in spite of over twenty years of having already practiced.

In 1875, as a young man he joined the 5th (Leith) Volunteer Battalion of the Royal Scots Guards[17] and largely on his initiative, a company of that regiment was raised in Portobello.

As a major he commanded the important tactical field days and was in charge of the defence of the Blackford Hill high point in Edinburgh during the post-Crimean War period with the resulting protracted Anglo-Russia tensions.

[33] Some of these were: Macadam was shot in the back and instantly killed on 24 June 1902, aged 46, in the laboratory of Surgeons' Hall by Daniel M'Clinton, a porter employed there.

The Scotsman reported TERRIBLE TRAGEDY IN EDINBURGH: Colonel Ivison Macadam and a Student Murdered, "The news, spread with great rapidity, caused the most profound regret.

At first, indeed it was hardly credited, for those who had seen Colonel Macadam only a few hours previously the picture of health and energy, it seemed impossible to believe that one who was so general a favourite had been laid low by a murderous hand.

Colonel Macadam’s death, the succeeding large military funeral, with wide participation from the general public, and the subsequent trial of the assailant received extensive coverage in the Edinburgh papers.

Shortly after Colonel Macadam’s son[35] also appeared, dressed in military uniform for the purpose of travelling to London along with his father.

The relatives… were completely overcome…and only remained for a few minutes…”[36] His funeral was reported to have been one of the largest seen in Edinburgh at the time with over 1000 troops, many carriages and tens of thousands of people turning out.

The Scotsman reported The Late Colonel Ivison Macadam: Imposing Public Funeral "With military honours befitting his rank … the funeral was an extraordinary demonstration of public sympathy … From the house the coffin was carried by eight sergeants to a gun carriage provided by the Edinburgh City Artillery and drawn by six horses with riders.

It was a four-mile procession from his house at Lady Road to Portobello Cemetery "to the solemn strains of the Dead March from "Saul" heard swelling in the distance… as the escort … proceeded in slow step..."[37] The Edinburgh Evening Dispatch reported Edinburgh Tragedy: Funeral of Colonel Macadam: Thousands of Spectators.

They had to clear the one end of Lady Road entirely … Marching in came a big representation of … the colonel’s own regiment … carrying their rifles reversed … the coffin saluted everywhere … by the crowds waiting for its passing.

Behind the gun carriage, which was drawn by six horses, was led the officer’s charger, which he rode only a few days ago at the inspection in Holyrood Park, while behind it again came several mourning coaches … Thousands of people—men women and children, many in working dress, some in holiday attire, a considerable number in mourning, followed the procession all the way to the Portobello Cemetery.

When the procession had traversed the four-mile route and reached the cemetery "… the Volunteers lined the walks, and the general public crowded every other inch of space"[38] The Scotsman concluded, “Amid the solemn silence the clergyman [finished].

While he had been charged with double murder, which was then a capital offence, his Defence pleaded "Not Guilty as a result of Insanity" (These symptoms are what today would likely be readily recognised and diagnosed as a not uncommon form of mental illness.)

"[40] There was no apparent motive for murder and while there had been overwhelming testimony of a disturbed mind, the jury obviously were not convinced that the defence had established the last form of insanity.

[41] She was the daughter of John Barkly Macdonald, of Stewart Hall, Bute where he farmed and was an owner of properties on the Island of Grenada, West Indies.

After his return to Scotland from Grenada he had married for a second time on 5 July 1844[44] in Rothesay, Mary McConechy—aged 33 who had been born at Windy Hall, Bute.

His parents were John and Sarah Macdonald of Trinidad and Grenada who were living at their Claremont Square, London house at the time of his father's death.

[45] William Macadam and his family first lived at 6 Brighton Crescent, Portobello and later at “Slioch” on Lady Road in the Craigmillar Park area on the south side of Edinburgh.

[49] W. Ivison and Sarah had six children (one dying in infancy): Mary Janetta Macadam, known as Myra (Born: 3 February 1880 at Stanley Road, Portobello.

[54][55][56] A mural monument with a bronze medallion portrait of Colonel Macadam in semi-relief with inscription plate was unveiled at the Royal Scots Dalmeny Street Drill Hall, Leith at the entrance to the building by Sir John Macdonald, Lord Kingsburgh on 21 December 1903.

[57] Among those present at the ceremony were Sir Charles Tucker, K.C.B., Commanding the Forces in Scotland and numerous army officers and men as well as Mr. Barkly Macadam, the eldest son of the deceased.

During the latter years of his life he was in closer association with him in practical work than any other man … he should never forget the energy and zeal he displayed and the extraordinary work he went through … if all the young recruits and all associated with the battalion in future looked on that monument with the earnest desire that they might do their duty as Volunteers with the same energy and zeal and ability … the corps would be sure to thrive and be an example to all Volunteer corps in the kingdom …Sir John then unveiled the monument, amid applause and handed it over to Colonel Salvesen, representing the battalion.

[61] On the following day, 22 December 1903, a monument in Portobello Cemetery was unveiled by Sir John Halliday, M.D., vice-president of the Royal College of Surgeons, at the Colonel’s grave.