Can anyone enlighten me ?

[brian1951]

No doubt you will remind me.

[RogerB]

He's a clever young stick that WTD. What's the prize? R-

[Walkingthedog]

Young stick? Much appreciated Roger.

[brian1951]

A box of sandstone offcuts.

[Walkingthedog]

Gosh I’m overwhelmed.

[brian1951]

Gosh I’m overwhelmed.

And so you should be, hand crafted by a master stonemason

[Walkingthedog]

Wow, where did you manage to find one of those?

[Roger O]

I think Walkingthe dog as the answer the bit we see is the fuse with the filament extending above and around the outside would have been the glass globe. I think I remember them when I was a child. We had one similar in my bedroom with a hefty filament in it to just give a low glow in the night.

[Mountain Goat]

Are you sure it is old? They make them like that today. (Halogen bulbs which have a larger outer part).

[collectors]

Nearest i have seen to this is a MBFU Mercury Vapour Lamp. They use them a lot in floodlights to get a white light instead of sodium bulbs that you get in old street lights that give the orange colour.