Thanks Sylvia, yes I had that. I have data from the 1871,1881 and 1901 census, have not looked at 1891 but that wont help with marriage. I have trawled the Scottish records again and found nothing for a marriage. I may be missing something if both Margaret and John had other christian names, something I've not found any info on but its a thought. I've looked at all Cottier marriages in the UK BMD between those dates and drawn a blank.