Hi John and Pete, sorry not to have replied more quickly. I have just a little to add to the very helpful notes which Pete has posted.
As mentioned in those notes, according to the 1861 census the “Ladies Seminary’” on Battle Hill was headed by the widow Margaret Charlton, and her daughter Elizabeth Charlton. Margaret Charlton later became the Mrs. Alexander who was heading the school at the time the Gibson daughters were pupils there.
The 1861 census also lists two children who were boarders and “scholars” (presumably more children attended as day scholars) and 3 sisters in their early twenties are listed as boarders and “pupils’”- which I think must mean Pupil Teachers. One of those was Elizabeth Walton, who shortly afterwards married John Pattison Gibson; she and John subsequently sent their own daughters to the school – the reason for my original query. So the Ladies’ Seminary was a family affair in more ways than one!
Apologies for adding a stray digit to one of the dates in my original query – it should have read 1868- 1879.
Cheers – and Happy New Year,