Talk:Traditional French units of measurement

Proper English basis for comparison

I changed the first sentence under History to give the article on "English units" as the direct comparison to the French units being discussed in this article. The customary English units would be the direct comparison to the French royal units in both time period and comparable historical evolution. US customary units would also be of interest, but are based on and their article linked to, English units. So I didn't add that.

I left the previous comparison to the Imperial System of units in parentheses. This system was a later rationalization of English units, taking place a full generation after France had replaced royal units with the metric system, and so is less authentic as a direct comparison. But still useful second link. Random noter (talk) 23:28, 10 April 2018 (UTC)

"Traditionally, the livre was defined as exactly 1/70 of French cubic foot"?

The article currently contains a weird claim, without a reference: "Traditionally, the French pound (livre) was defined as the mass of exactly ​1⁄70 of a French cubic foot of water. When the kilogram was defined, the knowledge that a pied du roi cube filled with water has a mass of exactly 70 livres was apparently lost." The claim of this being the "traditional and exact definition" was introduced in 2007 (diff). I didn't find a reference in support of it. Instead, sources say "From approximately the fifteenth century until the adoption of the metric system in August 1793, the official system of weights employed in France was called the "poids de marc" or mark weights, having for its primary standards the "pile de Charlemagne." Constructed some time between the middle of the fourteenth and the end of the fifteenth centuries, the principal weight - the "livre poids de marc" or pound by park weight of 0.4895 kilograms - was one of a series of 13 copper cup weights fitted one into another that totaled 50 marks or 25 pounds (12.235 kg)." (Zupko) The claim seems to be nonsense that should be removed. Ceinturion (talk) 12:25, 10 July 2019 (UTC)

• I agree, this makes no sense. Traditionally, units of mass were always defined in terms of reference weight pieces. Definitions of mass in terms of the mass of water of a specified volume at a specified temperature and pressure(!) only became popular around the time people started developing the metric system. Let's just leave it out. Hans Adler 17:44, 10 July 2019 (UTC)
  • PS: Actually, now I seem to remember there were some exceptions, but I don't think this is relevant to France. The definite answer can probably be found in Weights and Measures in Scotland: a European Perspective by Connor and Simpson. Although it focuses on Scotland, it has a wealth of in-depth information for most of Europe and was the best available source for this when I brought the article Apothecaries' system into its current shape. Unfortunately, the book is not available in my current university library. Hans Adler 08:05, 12 July 2019 (UTC)
    • Do you read French? Try these:
      • Marc at the Internet Archive
      • Livre at the Internet Archive
      • Garnier, Joseph (1841). "Livre". In Guillaumin, M. (ed.). Encyclopédie du commerçant: Dictionnaire du commerce et des marchandises. Vol. 2. Paris: Guillaumin et Cie. pp. 1355–1356. {{cite encyclopedia}}: Invalid |ref=harv (help)
    • Jonathan de Boyne Pollard (talk) 18:35, 12 July 2019 (UTC)
• That is a refactoring. It was introduced in 2006 by a different person. Jonathan de Boyne Pollard (talk) 18:56, 11 July 2019 (UTC)

François Cardarelli's Encyclopaedia

This has been discussed elsewhere in Wikipedia, and several people are of the opinion that whilst it is good for SI units it is riddled with subtle errors when it comes to non-SI non-English stuff. I can add a data point to this opinion. Cardarelli has just two tables of old French weights, noted as specifically the Parisian ones, oversimplifying things as much as this very article used to. The first has a "Lot" column that is a purported unit not mentioned in any French-language source that I have just cited, including Saigey's fairly thorough Traité de métrologie. That's because it's not a Paris measure of weight at all, or even a French one; it is a subdivision of the marc d'Augsbourg, a German measure. This book might not be a good thing to be pointing readers to. Jonathan de Boyne Pollard (talk) 02:29, 14 July 2019 (UTC)

My notes on the Cardarelli book are here: User:Imaginatorium/Cardarelli. Imaginatorium (talk) 14:28, 6 November 2019 (UTC)