ELD4930513 The discovery of glass by Egyptians using pieces of natron, a salt used for the preservation of mummies, as support for the cauldron in which they were cooking, circa 2000 BC (History of glass, egyptians using natron used in Egyptian mummification used along with sand and lime in ceramic and glass-making, 2000 BC) Engraving tiree about ??????Customs Gauloises??????by Madame de Renneville 19th century Private Collection; (add.info.: The discovery of glass by Egyptians using pieces of natron, a salt used for the preservation of mummies, as support for the cauldron in which they were cooking, circa 2000 BC (History of glass, egyptians using natron used in Egyptian mummification used along with sand and lime in ceramic and glass-making, 2000 BC) Engraving tiree about ??????Customs Gauloises??????by Madame de Renneville 19th century Private Collection); Photo by The Holbarn Archive.