My grandpa gave this large bulb can anybody tell me what it is.

that would be a 750 watt self ballasted mercury lamp. It doesn't need a ballast and will run off standard 120 volt supply it produces 14,000 lumens and has rated life of approx 16,000 hours VERY COOL FIND!!!

thank you

would i risk the lamp powering it up or should i not

would i risk the lamp powering it up or should i not

If it was me, I'd go for it. To me, a lamp is meant to be lit, not just looked at  

But it's up to you, I certainly wouldn't see any risk in lighting it, just make sure the supply cable is the correct rating and you use the appropriate fuse.

Just a thought, could you upload those photos to the gallery, it makes them easier to view, thanks 

i lit it up and it's brilliant sorry no pics to bright for my camera.

i lit it up and it's brilliant sorry no pics to bright for my camera.

That's a pity, I agree it can sometimes be hard to get good pictures of lit lamps. We definitely need a new camera here, the phone is all very well but it doesn't have the control you can get with a good SLR  

how about this

Those are good