Flexible glass is an alleged lost invention from the time of the reign of

Tiberius Caesar Tiberius Julius Caesar Augustus (; 16 November 42 BC – 16 March AD 37) was the second Roman emperor. He reigned from AD 14 until 37, succeeding his stepfather, the first Roman emperor Augustus. Tiberius was born in Rome in 42 BC. His father ...

. It may also refer to a form used today in

fiber optic An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair. Optical fibers are used most often as a means t ...

cables, though it is unknown if they are the same material.

History and mythology

Supposedly, the inventor of flexible glass (''vitrum flexile'') brought a drinking bowl made of the material before Tiberius Caesar. The bowl was put through a test to break it, but it merely dented, rather than shattering. The inventor repaired the bowl very easily with a small hammer, which he pulled from a pocket in his toga, according to Petronius. After the inventor swore that he was the only man alive who knew the manufacturing technique, Tiberius had the man beheaded. He feared that the glass would devalue

gold Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile me ...

and

silver Silver is a chemical element with the symbol Ag (from the Latin ', derived from the Proto-Indo-European ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical ...

, since the material might be more valuable. The account is most popularly related by two compilers,

Pliny the Elder Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, naturalist and natural philosopher, and naval and army commander of the early Roman Empire, and a friend of the emperor Vespasian. He wrote the encyclopedic ' ...

(, Naturalis Historia XXXVI.lxvi.195) and Petronius (, ''

Satyricon The ''Satyricon'', ''Satyricon'' ''liber'' (''The Book of Satyrlike Adventures''), or ''Satyrica'', is a Latin work of fiction believed to have been written by Gaius Petronius, though the manuscript tradition identifies the author as Titus Petr ...

'' 51). Pliny claims that the story of flexible glass is "More widely spread than well authenticated." Petronius's work is more dramatized and satirical. Pliny and Petronius's story is retold by Isidore of Seville (, Etymologiae XVI.16.6, ‘De vitro’), which in turn is included in pseudo-Heraclius's 13th century collection of technical recipes.

Modern usage

In the modern era, flexible glass is used in

cables and cannot be smashed with a hammer. It is extremely pure glass, manufactured with few defects and a pristine surface. In 2012, Corning Inc. introduced Willow Glass, a flexible glass based on

borosilicate glass Borosilicate glass is a type of glass with silica and boron trioxide as the main glass-forming constituents. Borosilicate glasses are known for having very low coefficients of thermal expansion (≈3 × 10−6 K−1 at 20 °C), m ...

. In 2016,

Schott AG Schott AG is a German multinational glass company specializing in the manufacture of glass and glass-ceramics. Headquartered in Mainz, Germany, it is owned by the Carl Zeiss Foundation. The company's founder and namesake, Otto Schott, is cre ...

introduced a similar flexible glass product.

References

{{reflist , refs= {{cite book , title=The Etymologies , author=Isidore of Seville , translator=Stephen A. Barney , translator2=W. J. Lewis , translator3=J. A. Beach , translator4=Oliver Berghof , year=2006 , publisher=Cambridge University Press , isbn=0-521-83749-9 , page=328 {{cite web , url=https://blog.cmog.org/2015/05/28/part-1-why-is-optical-fiber-flexible/, title=Why Is Optical Fiber Flexible?, last=Kuhn, first=Jennifer, date=May 28, 2018, website=Corning Museum of Glass, access-date=March 17, 2021 {{cite web , url=https://www.cnet.com/news/schott-flexible-ultra-thin-glass-bends/ , title=This glass can bend tens of thousands of times without breaking , last=Hollister , first=Sean, date=February 17, 2016 {{Citation, last=Spillman, first=Jane Shadel, chapter=Corning Glass Works, date=2018-01-12, publisher=Oxford University Press, doi=10.1093/gao/9781884446054.article.t019551, title=Oxford Art Online Glass engineering and science History of glass Glass types Greek inventions Lost inventions