Set of metal rods: Heat-sensitive paint changes color.

Set of various metal rods: Heat-sensitive paint changes color. Steam is passed through a metal tube connected to 6 metal rods (Lead,Tin, German Silver,Brass,Aluminum,Copper). Each rod conducts heat at a different rate. A temperature sensitive paint on each rod changes color from yellow to red. NOTE: At Pimentel, a silver rod is used instead of the tin rod. CONDUCTION.