Born "On the Ocean"

The 1850 census asked for the place of birth, and a child born aboard ship was often written down as "At Sea" or "On the Ocean". The man listed first, William McCann, was born in Ireland and Margaret, 11, in "Del" (Delaware), so the family most likely crossed the Atlantic around 1831 or 1832, when Mary was born, and was in Delaware by about 1839. The 1850 census does not name relationships, so treat "father" and "sister" as likely, not proven. The short dash under "Ireland" is a ditto: the older Mary was also born in Ireland.