A portable industrial search or spot lamp, probably dating from the 1930s onwards, and possibly ex military in origin. I have only ever seen this exact design once before (see last pic, Ancient Lights film prop hire company has two), and it's a stunning design and very solidly built. 40cm tall overall, and the light is approx. 20cm diameter, so a fairly big unit.

I haven't tested it, but as it is just a wire to a bulb holder I can't imagine it doesn't work, and if it did would be very easy to fix. This is a really stunning piece and would look great as a feature piece in an industrial style setting (house, hotel, cafe etc), or would also make a great prop for a film company. Only unwillingly for sale due to loss of storage, I have advertised at what I feel is a fair price and won't be upset if I have to find space for it.
That said, I have promised to try and make as much space as I can, so this is your chance..