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The French physicist and chemist Joseph Louis Gay-Lussac (1778-1850) defined the Gay-Lussac law of uniform thermal expansion of gases, named after him. According to this law, at constant pressure all gases expand by 1/273 of their volume when heated by one degree Celsius. He also developed a system that represents the alcohol content in degrees (°). The amount of pure alcohol in 100 litres of wine is given, measured at 15 °C. This system is still used in the Anglo-American world today, mostly in the abbreviation G.L. The value in degrees corresponds numerically to the volume percent. For a list of the complex of topics, see also Units of Measurement.

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Andreas Essl

The glossary is a monumental achievement and one of the most important contributions to wine knowledge. Of all the encyclopaedias I use on the subject of wine, it is by far the most important. That was the case ten years ago and it hasn't changed since.

Andreas Essl
Autor, Modena

The world's largest Lexicon of wine terms.

26,410 Keywords · 47,049 Synonyms · 5,323 Translations · 31,744 Pronunciations · 205,891 Cross-references
made with by our author Norbert F. J. Tischelmayer. About the Lexicon