James Ellis kept a Medical Journal from 15 May to 13 October 1831 -
The prisoners on their embarkation for the most part appeared in good health and spirits some few there were evidently desponding and ruminating on their fate; during the first fortnight all, with but one exception had suffered from sea sickness many very severely The winds at starting were strong and favourable for our proceeding to the southward so much so that on the 2nd July we came in sight of the Island of Palma, one of the Canaries, and as we proceeded on the voyage, the winds continued to favour us; crossing the Equator on the 20th of the same month and arriving in the vicinity of the Island of Tristan de Cunha on the 13th August. Up to this period we experienced with but little variation, mild and temperate weather. After this the weather turned bad and the hatches were required to be battened down in consequence of the water being taken in. 
James Ellis suggested that female prisoners should be employed on voyages in making their own clothes as a means of promoting good order. Since many of the prisoners were ‘quite callous to any disgrace or punishment’, Ellis suggested that part of the prison should be railed off, or provision made to rail off individual berths, and the worst characters locked up at night. On the Diana three berths were set up in this way and proved effective. He considered the confinement box supplied was insufficient since it held only one person and was unsuitable for any length of time in warmer climates. The only punishment the prisoners dreaded he thought, was having their hair shaved off but it only seemed to make them worse! 
James Ellis kept a Medical Journal from 6th September 1834 to 20 February 1835.
He found that catarrh and bowel complaints appeared almost immediately on their coming on board, and the sick list increased while at sea with many and various complaints and among them several cases of inflammatory fever, of which one prisoner, John Stroud died. Two more prisoners also died on the passage out. On the 17 December scurvy made it appearance and rapidly increased so much so that seventy seven cases of the disease had been under treatment.
James Ellis, R.N., kept a Medical Journal from 10 September 1837 to 21 February 1838. On the 7th October there was an outbreak of measles with two children of the Guard affected. Soon afterwards three more cases occurred. The surgeon reported that the cases were mild and easily treated.
Two children died on the passage out. The prisoners were reported to be generally healthy, although according to the surgeon they looked as if they had been scantily fed for some time before embarkation. 
He settled in Yass for a time and later returned to England