Fascinating! I have an Eliza Clarke born 1784, daughter of William Clarke, woolmerchant of Blarney Lane, Cork and Sarah Farren. Eliza married a Rice (I don't have a first name or any other details) and had two children at least, Anna Rice and George Nelson Rice, born 1806, dd 1827, who was buried in St Mary's Shandon, Cork. Anna Rice married a Robert Chambers, who was probably the tobacco importer with offices at 6 St Patricks Street, Cork in 1845 in Aldwell's Directory; a Robert Chambers was an associate of another Wm Clarke, (nephew of the above) of Clarke's Tobacco, whose address in 1856 was then 6 St Patricks Street. Does any of this match up with your research?