The 1841 census transcript has him aged 30 - a misreading of 50? - and born in Ireland.
Sarah is 40 and they have children Rebecca 20, John 15, William 13, Helen 11, James 10, Marrion 6 and a John Caglisham aged 5.
Address Cozie Glen, Kirkoswald.
There is also an Ancestry tree by Tina Burnside showing his arrival in USA 2 Aug 1849. Another tree says he was born in Ayrshire. You might want to check the US 1850 and 1860 censuses fir Allegany, Maryland (I don't have access).