Liquid nitrogen evaporates, and can cause violent oxidation of organic material. Ingestion of liquid nitrogen can cause severe internal damage, due to freezing of the tissues which come in contact with it and to the volume of gaseous nitrogen evolved as the liquid is warmed by body heat. In 1997, a physics student demonstrating the Leidenfrost effect by holding liquid nitrogen in his mouth accidentally swallowed the substance, resulting in near-fatal injuries. This was apparently the first case in medical literature of liquid nitrogen ingestion. In 2012, a young woman in England had her stomach removed after ingesting a cocktail made with
Ice cream bar The Good Humor ice cream company say that confectioner Harry Burt invented the ice cream on a stick in 1920, and was granted a patent in 1923. Ice cream bar An ice cream bar is a frozen dessert on a stick or a candy bar that has ice cream in it. The coating is usually a thin layer of chocolate used to prevent the melting and dripping of ice cream. The ice cream bar is often confused with the popsicle, which does not contain any ice cream. Originally called "I-Scream-Bar", Ice cream bar, or, the Eskimo Pie chocolate bar was