Family writings describe Blanche Elliott Watson (Sydney, 9/5/1863 - 27/3/1919) as a good artist by the age of 17. It records how she beat close on a thousand competitors in "black and white" (pencil sketching?). Where could I find information about these exhibitions?
The reference to "in black and white" seemed sufficiently distinctive to use as a search term. Since Blanche turned 17 in 1880, the period 1875-85 seemed appropriate.
From The Sydney Morning Herald Thursday 12 January 1882 (page 5)
AT a meeting the Art Society of New South Wales, held on Monday evening last, Mr. Edward Combes, C.M.G., presiding, it was resolved to invite the members to send in by the 1st May next designs in black and white water medium for a picture of some Australasian subject. A premium of twenty guineas will be awarded for such design as may be considered suitable for reproduction for presentation to the subscribers to the society's next art union in connection with the third annual exhibition to be held in October next. The picture selected will be the property of the society.
Note however that on Friday 13 October 1882, there was a (very) similar announcement with a January closing date for entries. It is possible that these were regular events in Sydney's art circles.