Hi Prue,
The Brisbane Street pictures I have just seen on Picture Australia suggest Napoleon Cottage was already demolished. It had been a detached property, described in 1912 in the Sydney Morning Herald, in an article reminiscing about the 1860's thus:-
"Brisbane Street contained only three or four houses, notably among them a large cottage known as "Napoleon Cottage", which was for many years the residence of one of Sydney's old identities, Mr. Gregory Board, an old-time publican and timber merchant, who amassed a fortune. The neighbourhood at that time was not built upon, and consisted of open paddocks extending to the Old South Head-road (now Oxford Street) on the southern side of Mr Board's residence extending to Albion Street (Mr. Terry Hughes's property) and Surry Hills was vacant land used as paddocks for depasturing cattle ..."
The next week, a reader's letter to the editor remarked:-
"... but Mr. Stack is wrong about the Sheriff Gardens, that is, so far as the old Sheriff Gardens are concerned. They started from the end of Goulburn Street, and went right up to what I know as the slate quarry, now, I think, Riley Street. Mr. Gregory Board's property was on one side, and the Sheriff Gardens on the other side of a creek that ran from Surry Hills."
I must admit I was hoping too at least find a sketch.
Thank you very much for your efforts.
Peter.