Glass in History
In the Stone Age man used natural volcanic glass (obsidian) as a cutting tool.
While burning earthenware, artificial glass was discovered accidentally, through the combination of fire, sand and natron.
The oldest finding of artificially produced glass - glass pearls from the graves of Egyptian kings - came from the era of about 3500 BC.
The first hollow glass was produced in Egypt and Mesopotamia in about 1500 BC through the use of sand core technology.
The clay tablet library of the Assyrian king Assubanipal (700 BC) contains the oldest remaining glass recipe: “Take 60 parts sand, 180 parts ash from sea plants, 5 parts chalk- and you get glass.”
The discovery of glassmaker pipes and of glass melting ovens in about 200 BC revolutionized the manufacture of glass and made possible the production of flat glass.
The Romans expanded the art of glass making in Europe (up to about 300 BC). Between 1300 and 1700 forest glass kilns (migratory glass kilns) predominated in Germany.
Glass for eyeglasses was manufactured from about 1250, and simple microscopes and telescopes from 1600.
In Benediktbeuern, Joseph Fraunhofer (1787-1826) sought to bring glass melting under scientific control. He improved microscopes, telescopes and survey instruments.
In 1846, Carl Zeiss founded an optical shop in Jena and from 1866 together with Ernst Abbe commenced the building of optical instruments on a scientific basis. However something was lacking: glass with constant, pre-determinable optical properties.
In 1879 Dr. Otto Schott began to research the combination of components of optical glass. He informed the Jena Physicist Prof. Dr. Ernst Abbe as to his results.
In 1884 the Glastechnisches Laboratorium (Glass Technology Laboratory), which later became the Jenaer Glaswerke & Gen. was founded by Otto Schott, Ernst Abbe, Carl Zeiss and Roderich Zeiss in Jena.