A look at the 1881 census for Euphemia Wilson - a more restrictive search than Alexander resulted in:
-1 EnumDist 6 Page 26
655049 Old Monkland, Lanark, Scotland L
Dwelling: Kelburn Cottage Alexander WILSON Married 66 M Head Newbattle, Edinburgh, Scotland Registar Of Births Etc
Dwelling: Kelburn Cottage Alexander WILSON Unmarried 37 M Son Bothwell, Lanark, Scotland Iron Founders Clerk (Unemp)
Dwelling: Kelburn Cottage Euphemia WILSON Married 65 F Wife Lasswade, Edinburgh, Scotland
Dwelling: Kelburn Cottage Helen WILSON Unmarried 23 F Daughter Old Monkland, Lanark, Scotland Dressmaker
Dwelling: Kelburn Cottage Maria G. WILSON Unmarried 27 F Daughter Old Monkland, Lanark, Scotland School Mistress
although NOT a "Gunpowder dealer" for Alexander birth etc are about correct.
Looking for a death of Euphemia Gordon produces only one at Old Monkland in 1891 aged 75 while that for an Alexander Wilson (b1815) gave the attached result.
All from www.scotlandspeople.gov.uk
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