Hi CU
My GGF served in the 25th Regiment in the 1870s. They officially became a Scottish regiment in 1881, when one Scottish regiment became Irish and the 25th was given to Scotland, even then the headquarters was in Carlisle .
In my GGF’s day most of the men were English or Irish, as they spent a lot of time in Ireland. My GGF enlisted in Gosport and married in Ireland. I will be checking the Muster and Pay Lists for the 25th in a few weeks and will look up William Potts for you.
Ken