Hello all and thanks for the prompt responses.
These people are my great-grandparents and I already have info gleaned on-line. I know that my great great grandfather Peter/Pietro was in Castle Street in the 1840s. He founded the company but I don't know if he died and is buried in Dublin or back in Switzerland, where he originally came from. Frank Ceppi was my great uncle. I know his dates of birth and death but have no idea about his life. He seems to have been a rather secretive person. I don't know if he married. I would like to know why my great aunt, Mary Adelaide, died as a child - but although she is in the family plot in Glasnevin there is no record of her death - nor of her father, my great grandfather, Seraphin. It seems that burial records/death certificates were not as rigorous as they are nowadays. Any pointers will be gratefully received. many thanks. PS I'm new to this site so forgive me if I'm not doing things properly!