I got the impression that 'district' was much more localised than that. Otherwise, why would he have had to have his 'district' changed from Bathurst to Carcoar in 1850?
The original post was as a result of a query I made to the poster. Alexander is an ancestor of mine and I have been tracing him from his birth, through his parents death, his conviction, time in Parkhurst and his exile to Australia. He did serve a good deal of time in Parkhurst (1844-1849) and as has been pointed out only had a few months to serve.
I did contact the Cowra Family History Group who did a quick search but couldn't find any more information. Only that he had an unclaimed letter at the 'Post Office'. I guess I may pay for them to do a more thorough search and perhaps find out more about the letter. If it was from England I have a feeling it may help fill in a missing link if it still exists.
He did serve a good deal of time in Parkhurst (1844-1849) and as has been pointed out only had a few months to serve.
Unfortunately his sister didn't fair too well after their parent's deaths either and led a life of crime and impropriety.