Not sure why I cant see it on Ancestry but on Findmypast they are on the 1891 census. Alexander is gone but his wife is listed as married (on 1901 census she is widowed). It's RG12, piece 487, folio 116, page 2. I've also seen an Alexander A Lister on 1891 census in Lancashire (Chorlton on Medlock, Manchester) who calls himself an engineer, traveller. He is married to an Amy Lister, quite a bit younger, who is an actress. Although this Alexander says he was born in Liverpool??? (RG12/3186).