I found this amazing piece of kit at the bottom of a drawer. I forgot it was there. I don't know what date it would be but probably just post-War or the 1950's. I put the bulb into the bedside lamp and soon remembered why it was languishing at the bottom of a drawer. It was absolutely useless. It gave out the equivalent light to a dim battery torch. It made reading or doing any activity difficult or impossible.
But that's not the point. The Mini-Miser (geddit?) is an early exercise in being green. It came at a price. 11/6d to be precise, but promised that' there would be 'fantastic savings on the Electricity Bill' and it 'quickly saves its own reasonable cost'.
'A boon to mothers needing a night light for young children or invalids..... ideal also for elderly people.'
The advert is more exciting than the product. But the Mini-Miser looks the part. It is possesses a certain 'je ne sais quoi, for a lightbulb'.
And, after 50-60 years, it still works. Amazing. Apple - you could take a leaf out of the Mini-Miser's book.