After fourteen years in the Royal Navy John Campbell was appointed as surgeon-superintedent on the convict ship William Jardine
in 1850. 
The William Jardine
departed 12 August 1850 and arrived in Van Diemen's Land 14 November 1850 with 260 male prisoners.
The National Library of Australia
notes and following records:
Records written or assembled by John Campbell during the voyage to Australia on the William Jardine
comprising: Diary 15 July to 21 Nov. 1850, noting daily routine of the surgeon, some incidents with the convicts on board, land sightings and the weather.
List of the 261 male convicts on board, compiled by John Byron, a convict sentenced to ten years transportation for forgery. The list gives names, age, marital status, birth place, sentence, crime, original trade or occupation, conduct in prison, whether the could read or write, years of separate confinement and public works, conduct on board, height and sometimes weight on embarkation.
List of 'General regulations to be observed by prisoners on board the William Jardine', and a list of overseers, constables, cooks, barber and clothesmen.
Notes by Campbell on the health of the convicts, guards and their families summarising the symptoms and treatment of the most common diseases.
Drafts of letters by Campbell to officials in Hobart and London, Nov. 1850 and May 1851 describing the health and conduct of the convicts and guards who had arrived on the William Jardine.
Notes Filmed as part of the Australian Joint Copying Project by the National Library of Australia and the State Library of New South Wales. National Library of Australia holds microfilm master. Australian Joint Copying Project miscellaneous series M385. 
John Campbell's Correspondence
From Dr. Campbell, Surgeon-Superintendent of the 'William Jardine:'
'London, April, 1851.
'I beg leave to acquaint you that I landed from the 'William Jardine' convict ship at Hobart Town, on the 21st of November, 1850, 260 male prisoners in perfect health, and the majority seemingly much improved by the voyage.
'I may observe that, in the management of the prisoners, a mild but firm plan was pursued, and I soon had the satisfaction to see my orders executed with willingness and alacrity. Measures were taken to employ them at work in various ways; and schools were also established under the religious instructor. By such means general good health was maintained, and the greatest harmony and good feeling prevailed amongst them.
Before leaving England three of the twelve Incorrigibles who had been embarked effected an entrance into the store-room by the chain-locker and stole two hams. As the case was clear against them, after a full investigation, I deemed it requisite to make an example, and ordered them to be flogged in presence of their companions, and two from each mess in the main prison. From that time the conduct of these twelve men was remarkably good, and I was soon enabled to release them from their irons. The treatment of these men seemed to have great effect in controlling the other prisoners, as many 'of them in writing to their relatives and old associates alluded to the difference of their positions.*
Punishments and coercive measures were, therefore, very seldom necessary, and any mark of kindness in sickness or at other times seemed to be much appreciated.'
'The superintendent of the Prisoners' Barrack at Hobart Town, in alluding to the prisoners from the ship 'William Jardine,' states, 'I was struck with the steadiness and respectful demeanour of these men when first received, and, although a few of them have since committed irregularities, I have every reason to feel satisfied with the general conduct of the majority.' I may add that nearly all seemed very desirous for employment, and, as a considerable number were engaged before I left the colony, I confidently hope, from their behaviour when under my charge, that many will live to become good and useful members of society.
* Incorrigible prisoners, destined for probationary discipline in Norfolk Island, are embarked in irons, and are kept separate from others during the voyage 
On his return to England in 1852, John Campbell was appointed to the Dartmoor convict prison and later to the Woolwich Invalid hulks and the Woking Invalid Prison including the lunatic wing. 
John Campbell, residence Knap Hill, 66 years of age and a widower, place of birth Scotland. Occupation is recorded as M.D. . His 18 years old son John resided with him and is a medical student; daughters, Elizabeth, unmarried age 23; Margaret unmarried age 21 and Jane unmarried age 19. The family have two domestic servants.
In 1884 John Campbell published Thirty years' experience of a medical officer in the English Convict Service
, London: T. Nelson and Sons 1884.
Notes and Links
More about John Campbell at Woking Invalid Prison Blog
John Campbell is listed in the Medical Registry, Residence Knap Hill, Woking, Surrey.
Lic. R. College Surgeons Edinburgh 1834;
M.D. University K. College Aberdeen 1846.
 National Library of Australia
 Extracts from the Reports of Surgeons-Superintendent during the voyage.....Report on the Discipline and Management of the Convict Prisons. 1850 By Great Britain. Surveyor-General of Prisons
 Campbell, John, Thirty years experience of a medical officer in the English convict service
. London: T. Nelson Sons, 1884...Read the publication at Internet Archive