I should have mentioned that. It is the Glasgow Electoral Registers on An...try. I am an An...try member but I usually get it more quickly by googling: "An...try - Glasgow Electoral Registers" and the main page comes up right away. It is very simple to use. You may well have to be a member of the site to use it. You just type in a name, plus a date, (I don't even put a date!) and click search.
It runs from about the mid 1800's to about 1962, if I remember correctly.
It is quite a useful site, but only gives very brief details. If it is a common name you are looking for, like John Smith or Thompson etc, it is much more difficult to find who you are looking for, because an awful lot of possibilities come up.