mcgarrell on Family Tree Circles

he came from ireland to newcastle upon tyne and was married in 1832 to Ann Adamson.
he had changed his surname to McGirl in order to get work, no one knows what the original surname was only that the family is related to the mcgirls.
after his death his sons myles and john changed the name to mcgarrell when they grew up.
john (son) family later changed it to McGaul.

I just would like to know what our original surname was, did he come with family or on his own. not knowing the original surname makes it imposible to trace the family back further. any help would be appriciated
kathleen

he came from ireland to newcastle upon tyne and was married in 1832 to Ann Adamson.
he had changed his surname to McGirl in order to get work, no one knows what the original surname was only that the family is related to the mcgirls.
after his death his sons myles and john changed the name to mcgarrell when they grew up.
john (son) family later changed it to McGaul.

I just would like to know what our original surname was, did he come with family or on his own. not knowing the original surname makes it imposible to trace the family back further. any help would be appriciated
kathleen