The news item appeared in the Adelaide Observer on 1 April 1871.
“A Sorrowful Ending. – There will be general regret at hearing that Wieland, one of the clowns in Mr. Burton’s travelling circus, who was well known in Adelaide, committed suicide at Castlemaine after having quarrelled with the proprietor of the circus and been discharged.”
I found a death record in Ancestry.com in the Death Index for Australia. It indicates that John B. Wieland was about 30 at the time of his death. Victoria registration #571.