Nope, 100W bulb, those things are typically rated for 60W or less.
Yep, it must have been purely the heat. For anyone who can't make it out, the marking on the reflector does indeed say "Max. 60W."
I've never seen one of those made of plastic...heck, the metal and glass ones cost about $4! That's plenty cheap enough for me.
Even with our inflated British prices these are about as cheap as you can get. I've seen them in the DIY stores for around £5. In my trade catalog they're listed at £1.45 (about $2.60) plus tax!
Yes they do come in plastic versions, polycarbonate, to be exact.
Or polypropylene. I'm no chemist, so I'm not sure about any significant differences in the composition.
Paul, are you allowed to dangle light fixures from a cord stapled to the wall, with no box like that in the UK?
No, that's just how far I'd gotten in removing it when I remembered I had my camera with me.
It was actually screwed to the soffit board, hence the scorch marks you can see at the top of the first picture. I can see how that looks like a staple on the cables, but it's actually a rubber grommet which was in the end the fitting.
Boxes are seldom used behind any light fittings here, except on conduit work. In fact the general method of connecting to lights is one aspect of British wiring which I find less than ideal.
