Conversation so far:
Why did Thomas Mitchell undertake his first expedition?
George Clarke claimed a river called Kindur flowed in New South Wales. Charles Sturt believed the Murray-Darling system formed the main river system. Mitchell wanted to prove Sturt wrong.
What year did Thomas Mitchell begin the first expedition?
Thomas Mitchell set out on 24 November, 1831.
Was Thomas Mitchell correct in his belief of the main river system in New South Wales during the first expedition?
Mitchel was satisfied that there was no truth about the river Kindur claimed by George Clarke.

Question: Was there a long term effect?
Self-contained rewrite: Was there a long term effect of Thomas Mitchell's first expedition?