The giant Glasgow-built warship - she was 227m long, displaced 27,000t and bristled with armaments - remained in the North Sea for the war. In January 1918, Ferguson, having applied to join any vessel that was destined to join New Zealand naval resources - the New Zealand "station" - was assigned to HMS Veronica.
Another Glasgow vessel, Veronica, was a much more compact ship than Renown.
The coal-fired 74m sloop had a complement of 77 crew, and was one of the "Acacia class" of vessels built at merchant shipyards to ease pressure on ports laying down warships.
Named after flowers, the ships had reinforced bows as protection against mines.
Veronica had come out of a refit at Pembroke in Wales when Ferguson joined her in March 1920 prior to the ship sailing to join the NZ division of the Royal Navy. After passing through the Suez Canal and making a coaling stop at Colombo, Veronica arrived in Darwin on 11 July.
The next day, according to the ship's log, "90lbs beef lost overboard by accident".
Tragedy struck two nights later when, at 10.30pm Ferguson slipped and fell as he crossed the gangway to the ship.
A news item in an Australian newspaper reported that Ferguson struck his forehead heavily on the wharf timbers.
At 2am the next morning divers started searching for his body. The work was suspended two hours later, and resumed at 10am.
At 11.45am on July 15, Ferguson's body was recovered, according to the log.
At 5pm that afternoon, the young New Zealander's body was taken to Port Darwin's cemetery in Garden Rd and buried with full naval honours.
Veronica left Darwin the next day, headed for Sydney and finally reached Auckland on September 19.
Four years later, his family arranged for his remains to be exhumed and reinterred in the grounds of St Andrews Church in Epsom.
Even then, Ferguson's memorial misspelled his name and got the date of his death wrong by a year. Author Gerry Wright drew the mistakes to the notice of the Commonwealth War Graves Commission.
The polished granite, which Sublieutenant Ferguson shares with his father, also named Alexander, and his mother, Agnes, was corrected and reinstalled in March this year.