212 BC Death Ray!

[fighting_ignorant]

Ancient Greek and Roman historians recorded that during the siege of Syracuse in 212 BC, Archimedes (a notably smart person) constructed a burning glass to set the Roman warships, anchored within bow and arrow range, afire. The story has been much debated and oft dismissed as myth.

David Wallace, MIT professor, takes up the challenge:

http://web.mit.edu/2.009/www/lectures/10_ArchimedesResult.html
Cool.

[Bosda_Di_Chi_of_Tricor]

Been there, done that.

At least one, & possibly several, other Threads.
I am too lazy to search for em.

[CalMeacham]

I’m not:

Same Title and Everything!
http://boards.straightdope.com/sdmb/showthread.php?t=340395&highlight=Archimedes

Almost the same title, but earlier:

http://boards.straightdope.com/sdmb/showthread.php?t=339599&highlight=Archimedes