Recalling the Conditions for Thermal Cracking

Several people disguised as construction workers broke into the world-famous Louvre Museum in Paris on Sunday, cracking open display cases and stealing jewelry that once belonged to the Emperor Napoleon and his wife, officials said. At least nine pieces of jewelry of "inestimable heritage and historical value" were taken in the brazen heist, authorities said. The museum was closed for the rest of the day as "a security measure and to preserve traces and evidence for the investigation," officials