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 ice cream in the summer of 1790. The same records show president Thomas Jefferson having an 18 step recipe for ice cream. First Lady Dolley Madison, wife of U.S. President James Madison, served ice cream at her husband's Inaugural Ball in 1813. Small-scale hand-cranked ice cream freezers were invented in England by Agnes Marshall and in America by Nancy Johnson in the 1840s. The most popular flavours of ice cream in North America (based on consumer surveys) are vanilla and chocolate. In the Mediterranean, ice cream appears to have been accessible to ordinary people by the mid-eighteenth century. Ice cream