Familysearch.org shows the paternal line of Charlotte and Christian Purves going back to 1200.
However, take it with a grain of salt. There are couple of unnamed forebears, and it shows their eldest brother as David 1739 - 1883 (144 years of life, and being born 38 years before his own father!!)
I think a grain of salt is probably too optimistic - if whoever submitted it is a sloppy and careless as that, you cannot trust anything in that tree.