Career
David Laing speculated that he was John Mercer the younger brother of William Mercer who was also a parliamentary officer and author of "Angliae Speculum, or England"s looking-glass" (London 1646).
David Laing speculated that he was John Mercer the younger brother of William Mercer who was also a parliamentary officer and author of "Angliae Speculum, or England"s looking-glass" (London 1646).