The message
from Pam Moore contains these words:

So, Janet and Rusty, are you telling me it's Ok to turn the hose on my
plants in full sun, when I have many times heard the advice not to?

No. But it's got nothing to do with burning. It's the shock of cold
water on warm plant. It *MIGHT* do them some no-good.

Janet, which would you prefer to start a fire, leaves or metal?

Well, metal. Mix some steel wool with something dry and combustible,
strike a spark into it, and watch it go! (Or focus the sun's rays
through a lens on it.)

Also, in my experience lenses are convex too.

Yes, but droplets are globular. Condensing lenses are not.

Remember how still you had to keep the lens to burn paper? Walking in
the rain is a bit different?

Yes, you don't want to keep still while walking. Especially in the rain.

--
Rusty
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