The Roman gran - probably a barley grain (with about 0.065 grams; in the Middle Ages for example also a wheat grain with about 0.05 grams) - is the (12 × 576 =) 6912th part of the Roman Libra , or the (16 × 576 =) 9216. Part of the Mina. So it weighed exactly 47 mg .
The grain is the smallest classical English mass unit and is common to all three English systems common in modern times ( Avoirdupois , Troy and apothecaries' weight ). The usual pound counts 7000 grains , the apothecary and Troy pound exactly 5760 grains . In addition, some traditional units of mass in English colonies were redefined based on the grain , such as the Indian tola as 180 grain.
- 1 English grain = 64.79891 mg.
- 1 gram ≈ 15.43236 English grains.
The French grain was the 9216th part of the French pound. In 1799 the final decimal kilogram was determined to be 18,827.15 French grains . That means a French grain is equivalent to about 53.1148 mg (1 gr. / (18827.15 gr./kg) × 1,000,000 mg / kg).
- The unit of gran was also used for German coin weights . The gold gran was 1/288 Cologne marks . It also weighed sixteen grains. That's about 812 mg. In Grammateus Ayn new kunstlich buech which certainly vnd nimbly learns ... meticulously counting on kauffmanschucks (Nuremberg 1518) it says (E 1b): “Lautter goldt held 24 carats on the line, which carat ains held 4 grains” and in the Meißnischen land vnd Berg-Chronica des Petrus Albinus (1590), p. 126: "a marck fein goldt is 24 carat, one carat is 12 gren, three gren are one gran, 288 gren is a marck fein goldt"
- In the Nuremberg pharmacist weights , the gran (as elsewhere) is the 20th part of a scruple and the 5760th part of the pharmacist pound, i.e. about 62 mg. As the smallest pharmacist's weight after scruples, the gran appeared for the first time in the 12th century in the antidotarium Nicolai by Nicolaus Salernitanus, who divided the medical weight scruples into 20 grana (grains), and shortly afterwards in the Practica brevis by Johannes Platearius the Younger. In Wirsungs Artzneybuch of 1588 it says (30c): “Gran, you need barley grains heavily for it, are therefore formed Ga. In these, twenty are generally calculated for a scrupel . But because one finds the barley so perfect with Vns, especially that hard thirty, about forty, a scruple because of (= weigh), so it is appropriate that a perfect peppercorn is taken for I Ga, since then twenty even with one Э (ie scrupel) apply "
- According to Duden , a grain usually weighs around 65 mg. According to the Cologne mark, the (trial) grain accounted for 12.7 mg.
- Rarely also as length, area and body measurements (probably based on the width of a grain) with different measurements: 1 grain = 1/144 shoe = 2.03 mm (17th century), cf. Fischer, Swabian Dictionary, Vol. III 3, 788 and Wolff, Mathematisches Lexicon (1747), p. 601: “Gran ... in geometry it is in length the toe part of an inch, the hundred part of a shoe, and the thousand part of a rod ... in terms of its area it is the toe part of a belt inch ... in physical terms it is the toe part of a bar inch ... you tend to call a grain a line "
- Philip Grierson : Coins of the Middle Ages. Translation into German by Alfred P. Zeller. Munich 1976 (= The World of Coins. Volume 4), p. 314.
- Ambler Thompson, Barry N. Taylor: NIST Special Publication 811, 2008 Edition: Guide for the Use of the International System of Units (SI). (PDF) National Institute of Standards and Technology, March 2008, p. 50 , accessed on January 27, 2014 (50 is the page number shown on the page).
- In particular, barley grains, wheat grains and rye grains come into question.
- See also Carl Külz, E. Külz-Trosse, Jos. Klapper (ed.): The Breslauer Arneibuch. R [hedigeranus] 291 of the city library, part I: text. Dresden 1908 (= monthly sheet of the Goslar CV of natural science and medical associations at German universities. Years 3 and 4), p. 181 (“There are few weights in the area where you have to walk, scrupulus heats, and you have twenty grains of wheat”).
- Gundolf Keil : "The best advice is the icker toe can against genomen vte platearise". References to Ypermans Medicine. In: Geneeskunde in nederlandstalige teksten tot 1600. Koninklijke Academie voor Geneeskunde van België, Brussels 2012 (2013), ISBN 978-90-75273-29-8 , pp. 93-137; here: p. 110.
- Gran, das. In: Duden. Bibliographisches Institut GmbH, accessed on January 27, 2014 .
- Helmut Kahnt, Bernd Knorr: Old dimensions, coins and weights. A lexicon. Bibliographisches Institut, Leipzig 1986, licensed edition Mannheim / Vienna / Zurich 1987, ISBN 3-411-02148-9 , p. 394.