Oh god, you've just brought to mind a tale a friend told me. When he was an apprentice (which was quite a few years ago now), he was in lodgings with an elderly lady (he reckoned about 80) and her father who still thought nothing of going up on the roof with ladders. But they were rather deaf, so he rigged up the doorbell push to a light on the mantlepiece - and I suspect a few of you know ehre this is heading ...i think he means the original ones of these, the ones in the pic may be replicas
The bell push was an old porcelain job with brass button - and the brass button was connected to one side of the switch. And the mantlepiece light was straight off the mains Not one to be pressed in wet weather.
They were in my parents house when we moved there - hardly got used and eventually replaced with standard double sockets. Those 2A plugs are not very common, and weren't even back in the 80s. Though Woolies near my university sold them - most of the student rooms had them so there was a brisk trade, and also a second hand market when leaving.Item 9 on this page seem to be a more modern version.
http://www.plugsocketmuseum.nl/British1.html