At various times between 1871 and 1889 his occupation was listed as "bootmaker", "perfume manufacturer" and "preparer of microscopical objects".
In his later life he served as librarian, vice-president and committee member of the Field Naturalists Club of Victoria.
He spent the final year of his life in the Yarra Bend Lunatic Asylum, suffering from dementia and paralysis, apparently without any family or close friends.
[1] His scientific legacy consists of significant phytological collections, and several published papers.
His published papers are as follows: Despite his modest scientific output, it has been argued that "Watts should be remembered as the pioneer of freshwater phycology in Victoria", primarily because he was collecting freshwater algae at a time when very few others were doing so, other than incidentally.