Actually, it does exist. Just check the wikipedia episode list. I've even seen this episode, and it is definitely not a Christmas special.
The myths tested: Could a torture technique consisting of growing a bamboo through a victim's body have worked? Does dropping alkali metals in a water-filled bathtub result in a huge explosion? Does brandy, such as carried by Saint Bernards, really prevent hypothermia? Does lighting a piano on fire make it explode?
There does seem to be a torrent available that offers the Christmas special with the season 6 episode 21 name, but that's just an incorrect file. The actual episode does exist.
The myths tested: Could a torture technique consisting of growing a bamboo through a victim's body have worked? Does dropping alkali metals in a water-filled bathtub result in a huge explosion? Does brandy, such as carried by Saint Bernards, really prevent hypothermia? Does lighting a piano on fire make it explode?
There does seem to be a torrent available that offers the Christmas special with the season 6 episode 21 name, but that's just an incorrect file. The actual episode does exist.