So nearly a house fire!

[gareth h]

My daughter reported a burning plastic smell in her bedroom this morning, when she investigated her small make up mirror had focused the sunlight coming through the window (in west wales, I know!) onto the plastic frame of her full length mirror, melting it, we were all on our way out when she noticed it!

[normalbloke]

A good friend had a similar near miss with a small mirror left on the sofa. It managed to start something smouldering on the table next to it. It’s so easy to become complacent, how many of us leave reading glasses just thrown onto whatever surface is nearest without a second thought.

[996Type]

Crystals hung from windows and prismatic / mirrored picture frames etc also able to focus down the rays to combustible materials to cause fires. If you have any “rainbows” in the rooms in bright sunlight it’s a warning, as the sun tracks through the sky these can be focused onto whatever’s in the room…..

[Actual]

996Type said:

... any “rainbows” in the rooms in bright sunlight it’s a warning, as the sun tracks through the sky these can be focused onto whatever’s in the room…..

That sounds like a good tip

[dhutch]

gareth h]her small make up mirror had focused the sunlight coming through the window said:

Presumably a concave mirror.

[LivLL]

dhutch said:

gareth h]her small make up mirror had focused the sunlight coming through the window said:

Presumably a concave mirror.

Those and shaving mirrors are concave yes.

[The Gauge]

Remember those square panes of glass you used to find in front doors years ago, the ones with a raised circular pattern (were they called bullseye?) well apparently when people didn’t pick up their post from the floor in the morning the sunlight would be magnified by the glass and set fire to the letters.

The things you learn when you volunteer to attend your employers fire warden course because it meant finishing work early for that day!