Thomas Reid was born in Ireland in 1791 and educated in County Tyrone.  He was appointed Assistant-Surgeon on the Canopus in 1810.
He passed his examination at the Royal College of Surgeons in England on 7 May 1813 and was admitted to the Royal College of Surgeons in London in 1815.
Thomas Reid was a sincerely religious man who laboured earnestly to ameliorate the condition of the prison population of the country. In early life he drew attention to the conditions attending the transportation of convicts male as well as female, to the penal settlements in Australia. He showed how bad was the discipline to which they were subjected on board ship during their transference, and how atrocious were the arrangements made for their reception when they arrived in New South Wales. He strongly advocated that convicts should no longer remain idle, but should be employed in a rational manner. 
At the instigation of Elizabeth Fry he made two voyages as surgeon-superintendent on convict ships sailing to Australia.
Morley, to Hobart Town and Sydney in 1820 (female prisoners).
The Neptune departed the Downs on 20th December 1817 and arrived in Port Jackson on 5 May 1818.
The ship was kept clean, ventilated and also warmed by stoves if the occasion arose. Once the ship got underway Mr. Reid began to attend to the twenty three junior convicts, all of whom were under 20 years of age, some as young as 13. He mustered them all and questioned them individually and found to his dismay that only five could read and write. He immediately set up a school on board and placed the young men under the care of a convict appointed as schoolmaster. The school continued for the entire voyage and at the end each boy was literate
The prisoners by the Neptune were fortunate in having Thomas Reid as their surgeon on the voyage to Port Jackson. He was humane and treated the men fairly throughout the voyage.
Thomas Reid returned to England on the Neptune departing in June 1818. 
The Morley 1820
The Morley departed London on 22 May 1820 with 121 female prisoners.
Thomas Reid wrote to the editor of the London Times on 1st May regarding the women:
Female convict ship Morley,
Having lately noticed in several papers various accounts of the refractory conduct of 40 unfortunate female convicts in Newgate on the night previous to their being removed to the Morley, as well as communications to the same effect having been made to me since their embarkation, I think a few observations on the subject may not be unacceptable to the public; and if you think the following worth insertion in your paper, you are at liberty to make them public.
Of the behaviour of these women in Newgate I can say nothing, though I have great reason to believe it was not half so bad as has been represented: of their conduct here I am happy that it is in my power to bear honourable testimony. On first coming on board three or four of them showed some disposition to be unruly; but a timely rebuke, with a positive assurance that all irregularity of conduct would be opposed and punished, put an immediate stop to it.
Those who pretend to say that the humane exertions of Mrs. Fry and the committee of ladies have produced no beneficial change on the minds and morals of these misguided creatures, need only visit them here to be convinced of the fallacy of their assertions, by proofs more irrefragable than the most specious arguments of speculative logicians. They will find many of them reading the Scriptures with apparently devout attention, and I firmly believe real advantage. I am not ashamed to acknowledge, that I have given every exertion in my power towards establishing a system of religious behaviour amongst them; and therefore feel no hesitation in putting my name to this statement' 
The Morley arrived in Port Jackson on 30 September 1820. Thomas Reid's opinions of his charges had changed following months of a very difficult voyage.....
There were two of the females under my care, whose behaviour during the voyage was so profligate, that, besides the character with which they were handed over at the muster, I was induced to point them out to the notice of the Governor, with a request that they might be separated from the others; to this his Excellency paid immediate attention, and gave orders to that effect.
I mentioned the same matter, moreover, to the superintendent of convicts, who made a note of it in his book in my presence; yet, on that very same evening, these wretched creatures were permitted to go at large in the streets of Sydney, where necessity or their own abandoned propensities must have driven them to infamous practices. About one half of the female prisoners were disposed of in Sydney and its neighbourhood, and the remainder were kept in a separate place in the gaol, until an opportunity should offer for removing them to Parramatta, whither the governor had directed they should be sent by water, to prevent improper conversation with straggling prisoners of the other sex, who are continually infesting the roads.
It is to be remarked, however, that those whose behaviours or disposition had most frequently incurred censure on the voyage, and consequently least merited favourable report were singled out as the fittest objects for assignment, while many of those whose conduct had been uniformly deserving of approbation, whose names also were conspicuous for excellent character, were left to be transmitted to the Factory! 
Excursion in Sydney
In October Thomas Reid accompanied Governor Macquarie on his Tour of Inspection to the Western and Southern Countries that had been discovered by Charles Throsby.
Governor Macquarie remarked in his Journal - day 25. Octr. Waked quite refreshed – and perfectly free of Headache this morning - Our worthy good Travelling Companion Dr. Reid took his leave of us, and set out on his return to Sydney at Half past 5 this morning – having first taken an early Breakfast. The Revd. Mr. Cartwright and Mr. Meehan gave him a convoy for some miles on the Road. — We all much regret Dr. Reid's departure, as we found him a most agreeable, good humuored,[sic] and entertaining friend and associate. — He was, however, obliged to leave us here – being afraid of not overtaking his ship (the Morley) at Sydney in case he staid with us any longer. 
Return to England
Thomas Reid returned to England on the Guildford in October 1820 with other surgeons Robert Espie and Hugh Walker.
Thomas Reid revisited his native country in 1822 and made an extended tour through the central, northern, and southern parts of the island. 
Thomas Reid died at Pentonville, London on 22nd June1825. He was burid at St. Giles Without Cripplegate, London
Aug. 21. At Pentonville, in his 35th year, Mr. Thomas Reid, Surgeon in the Royal Navy. Mr. Reid was born and educated near Dungannon, in the county of Tyrone, Ireland. He was actively employed for many years in various parts of the world, from which he made occasional contributions to the Public Museums of Great Britain.
His conversational powers were of the highest rank, and his literary talents of no common order. He was the author of an interesting volume on his Voyages to New South Wales, and of a work entitled “Reid's Travels in Ireland,” which excited a strong sensation a few years since. For liberality of sentiment, correctness of description, and vigour and perspicuity of style, it merits the bighest praise.
In the circle in which Mr. Reid moved, he was justly admired for candour, manliness, and generosity ; and the sorrow excited by his early death is heightened by the recollection of his many acts of steady and uncompromising friendship, and sincere and cordial benevolence.
Thomas Reid was only thirty-five years of age when he died. Address Castle Street Station Square, London. He left a Will which was proved 4 July 1825. Those mentioned in the Will include:
Thomas Reid, father
Sister-in-law Ann Bell Fulton
Brother-in-law Captain Robert Fulton
John Liddiard Nicholas, friend
James Boyle, friend
Robert Reid, brother
Wife Eliza nee Fulton
 Interesting Descriptions of the Present Condition of the Colony of New South Wales; Including Facts Relative to the Management of Convicts of Both Sexes written by Thomas Reid and printed in the Morning Post 7 January 1822
 The Sydney Gazette and New South Wales Advertiser (NSW : 1803 - 1842) Sat 30 May 1818 Page 4
 The Times,  The Times, Wednesday, May 03, 1820; pg. 3; Issue 10923; col D