Found a bit more that may or may not be of use:
An online tree has Denison William Downes b 1827 and dying 1886, Leichart, NSW, aged 59.*
* added - spouse - Elizabeth Hughes (1835-1921)
Parents - William Denis Downes, b. Cork or London! (1801- 1865) and Mary Ann Driscoll b. London (1804-1891)
full details on Mundia.com
Gadget