Archibald Colquhoun Ross was on on the List of Gentlemen who appeared before the Royal College of Surgeons of Edinburgh who were fully qualified to practise the arts of Anatomy, surgery and Pharmacy and accordingly received Diplomas in August 1829. 
He was employed as Surgeon-Superintendent on the convict ship Susan in 1834.
Archibald C. Ross, M.D., died at Funchal, Madeira a week after his return to labour amongst the sufferers from cholera. He was 47 years of age. 
The circumstances of his becoming Surgeon Superintendent to the Susan were explained in his obituary:
On September 6th, at Madeira, died Dr. Archibald Colquhoun Ross, who obtained his licence from the College of Surgeons of Edinburgh, in 1829, but was obliged to repair to Madeira in the following year, on account of the failure of his health, where he practised during most of his life, having attempted in 1848-9 to practise as a physician in London, but being unable to support the rigour of our climate.
After the expulsion of Dr. Reilly from Madeira, for attempting the religious conversion of the Roman Catholic residents, Mr. Ross was obliged, with other foreign practitioners, to repair to Lisbon for a licence to practise, and there he obtained after examination, a doctor's degree in medicine.
Dr. Ross has given no written proof of the acquirements he was said to possess; but he has left, according to the evidence of a friend, who is himself a man of the same stamp, a brilliant example of that steady devotion to the path of duty which is, I trust, not unfrequent in our profession, and which has often been observed in persons of every class, in whom, as in Dr. Ross, the physical powers appear unequal to brave exertion and danger.
When Dr. Ross had resided three or four years in Madeira, with increasing practice, a convict-ship arrived, bound for New South Wales, whose surgeon had committed suicide a few days previously. The Consul was applied to by the captain for assistance, to prevent the necessity of his return to England, on which Dr. Ross immediately volunteered to take, what is at all times an anxious and very responsible charge, in addition to the medical duties of the ship.
On his return from Australia, he remained at St. Helena to supply the place of one of the East India Company's surgeons, who wished to go to England on furlough; and the presentation of a piece of plate to Dr. Ross by the governor, General Dallas, shows the sense he entertained of the manner in which his duties were performed.
Finally, while Dr. Ross was in this country for a short time last year, cholera commenced in a virulent form, in July, in Madeira, on which Dr. Ross immediately repaired to the scene, where he arrived on August the 30th, and, after great professional exertions, fell a victim to this disease on the same day of the following week.
His motive for his return to the island was thus expressed to a friend on the day after his landing: 'Should it please God to take my life in this service, I trust my wife and family will bow with submission, and feel that my duty called me. A doctor has no choice in such cases.' 
Notes and Links
1). January 14 1864. At Penzance, Cornwall, aged 20 Archibald Carne, second son of the late Archibald Colquhoun Ross, esq., M.D. 
2). At Hove, Brighton, Major Percial Robert Innes, H.M. Indian Army, to Mary Carne, eldest daughter of the late Archibald Colquhoun Ross, M.D. of Madeira.