We did a demo of this toy outside for a bunch of schoolchildren, several
groups of them for a couple of hours. At some point we noticed the plastic
was melting on the top surface !!
The Sun was close to being in focus, and delivering too much energy in one
spot, which slowly moved along.
mike
--
Mike Moloney, Physics & Optical Engineering Department
Rose-Hulman Inst of Tech, 812 877 8302
moloney@rose-hulman.edu http://www.rose-hulman.edu/~moloney