Alexander Watson was one of the two sons and four daughters of John Watson of Freehall, Castlerock, County Londonderry, and his wife Mary. He graduated MD (University of Edinburgh) in 1847 his thesis being ‘On acute pleurisy’, and with the Membership of the Royal College of Surgeons of Edinburgh (MRCSEd.). On 16 January 1848 he entered the Naval Medical Service as assistant surgeon and was soon warranted as surgeon on HMS Highflyer, saw service in the Crimean War and was mentioned in dispatches for his commendable skills during an outbreak of cholera in the fleet at Varna. Subsequently he saw active service in the principal naval engagements and operations in the Black Sea which included the bombardment of Sebastopol and the capture of Kertch for which he received the Crimean and Turkish medals and the Sebastopol clasp. He was promoted staff surgeon on 2 December 1855 and posted as an additional medical officer to the flagship of the Commander-in-chief of the Mediterranean station, and in this rank was appointed to HM screw sloop Cormorant under the command of Thomas Saumarez which in May 1858 took part in the capture of the Peiho forts which allowed passage for Lord Elgin to proceed up-river to sign the Tien-tain Treaty. The following year (1859) this treaty required ratification, but the Chinese refused passage to the envoy (Sir Frederick Bruce KCB), and when a flotilla, including Cormorant tried to force a passage, it was repulsed, Cormorant and two other vessels were sunk, and Watson was among those wounded. For his skill and courage during the action, Watson was awarded the China medal and Taku clasp, and after recovering from his own wounds he was put in charge of the seriously wounded on their return to England.
In 1868 Watson, now staff surgeon on the Commodore’s ship HMS Challenger, proceeded to Australia as part of the fleet accompanying Prince Alfred, Duke of Edinburgh and Saxe-Coburg Gotha, Queen Victoria’s second son (and fourth child), on his tour of the colonies. The prince himself had been promoted captain of HMS Galatea (on 23 February 1866) and this was the first ever visit to Australia by a member of the British royal family. On 12 March 1868, at Clontarf on the shore of the Midddle Harbour in Port Jackson, Sydney, New South Wales, the prince was mingling with guests at a public picnic when he was shot in the back in an assassination attempt by an Irishman, Henry James O’Farrell, an ardent ‘Fenian’. Watson was present, gave emergency treatment and two days later (14 March) with the assistance of the surgeon from the Galatea (Dr. Young) and others including assistant surgeon Powell, successfully removed the bullet which had in fact been deflected by a rib from damaging more vital organs. O’Farrell was convicted and hanged on 21 April 1868. Watson was mentioned in dispatches and was specially promoted Fleet Surgeon (on 4 July 1868) and later appointed to the prince’s ship HMS Galatea remaining with it until it returned to England after visits to India, China and Japan. In 1875 he was appointed to HM Indian Troopship Serapis on which the Prince of Wales (elder brother of Prince Alfred and ‘heir apparent’ to Queen Victoria) was sailing to India, and on his return was further promoted (on 5 July 1878) to Deputy Inspector-General, and the following year was appointed to be in charge of Haslar Royal Naval Hospital, Gosport, retiring finally on 21 July 1881 with the honorary rank of Inspector-General of Hospitals and Fleets
On retirement Watson moved to rooms in the Charing Cross district of London where he frequented the Army and Navy Club moving later to Liverpool where he lived in Hartwood, 25 Green Lane next door to his sister, Sarah Hill at number 23. He died on 17 April 1902 of hepatic cirrhosis and is buried in Anfield Cemetery, Liverpool. He was unmarried, the only one in his sibship of six to be so. Little is known of his personal or social life but he is said to have been courteous, genial and kind-hearted, popular with his colleagues and liked by his patients, “his rooms [in London] much frequented by former shipmates and friends….always ready to assist the necessitous…[and] it was a surprise to many naval officers familiar with Dr Watson’s services that he received no special recognition of them from the Admiralty” (British Medical Journal).