I have boiled water and cooked stuff in home-made solar cookers similar to
what you describe.  Check out:
http://solarcooking.org/

Edward

At 09:58 PM 3/9/2003, you wrote:
>Has anyone ever boiled water using a large magnifine glass as the top of a
>box that contained the pan of water???
>
>Kinda like a parked car retaining heat...
>
>
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