in both metres and
pied royal These definitions use the Paris definitions for the
coutume of Paris, and definitions for other
Ancien régime civil jurisdictions varied, at times quite significantly.
Length The medieval royal units of length were based on the
toise, and in particular the ''toise de l'Écritoire'', the distance between the fingertips of the outstretched arms of a man, which was introduced in 790 by
Charlemagne. The
toise had 6
pieds (feet) each of 326.6 mm (12.86 in). In 1668 the reference standard was found to have been deformed, and it was replaced by the
toise du Châtelet which, to accommodate the deformation of the earlier standard, was around 11 mm (0.56%) shorter. In 1747 this
toise was replaced by a new
toise of near-identical length – the
Toise du Pérou, custody of which was given to ''l'Académie des Sciences au Louvre''. Although the
pouce (
inch),
pied (
foot) and
toise (
fathom) were fairly consistent throughout most of pre-revolutionary France, some areas had local variants of the
toise. Other units of measure such as the
aune (
ell), the
perche (
perch or rood), the
arpent and the
lieue (
league) had a number of variations, particularly the
aune (which was used to measure cloth). The
loi du 19 frimaire an VIII (Law of 10 December 1799) states that one decimal metre is exactly 443.296 French
lines, or
3 pieds 11.296 lignes de la "Toise du Pérou". Thus the French royal foot is exactly metres (about 0.3248 m). In
Quebec, the surveys in French units were converted using the relationship 1
pied (of the French variety, the same word being used for English feet as well) = 12.789 English
inches. This makes the Quebec
pied very slightly smaller (about 4 parts in one million) than the
pied used in France. • The French
typographic point, the
Didot point, was of a French inch, i.e. two royal points. The French
pica, called
Cicéro, measured 12 Didot points or inch.
Area Volume – liquid measures Volume – dry measures Weight Charlemagne's system had 12
onces (
ounces) to the
livre (
pound). Between 1076 and 1093
Philip I (1052–1108) instituted a system of
poids de marc (mark weight) used for minting coin, with 8
onces to a
marc.
Jean II (1319–1364) constructed a new standard of measures, including a
livre actuelle ("current" pound, also known as a
livre de poids de marc or "mark weight" pound) of 2
marcs, i.e. 16
onces. The Charlemagne 12-ounce
livre became known as the
livre esterlin ("true" pound) in order to distinguish it. ″
Esterlin″ was an Old French word (ca. 1190, Anglo-Norman dialect) that referred to Scottish coin (sterling, or ″denier″). As references cited later on this page show, its application changed over time in accordance with the changing historical context, though it is not current in Modern French. The
livre actuelle could be sub-divided into 2
demi-livres (half-pounds), 4
quarterons, or 8
demi-quarterons. Conversely, there were 100
livres in a
quintal (cf. English
hundredweight). The fractional parts of an
once had different names in
Apothecary measure (used in medicine) and measure of precious metals, but the fractional ratios were themselves the same: 1
once was 8
drachme (Apothecary, cf. English
dram) or
gros; 1
drachme/
gros was 3
scruples (Apothecary, cf. English
scruple) or
deniers, and 1
scruple/
denier was 24
grains. This makes 384
deniers in a
livre in weight measure, which contrasts with the old
monetary livre in France which was divided into 240
deniers. Jean II's standards are preserved in the Conservatoire Nationale des Arts et Métiers, which also holds a set of later-still physical standards from the 15th century, the so-called
pile de Charlemagne. This
pile defined the weight of 50
marcs, i.e. 400
onces, and thus 25
livres actuelles, or 33
livres esterlins. It had been kept in the royal palaces originally. In 1540
François I (1494–1547) had transferred it to the
Cour des monnaies, where it had been held in a cabinet with three locks, whose keys had been held separately by the president of the Cour, one of its counsellors, and a clerk. The thirteen individual pieces that made up the Parisian
pile de Charlemagne comprised an outer containing cylinder nominally weighing 20 marcs, and a set of hollow nesting cups within, topped with a filled weight as the smallest piece. The heaviest cups were nominally 14, 8, 4, and 2
marcs, sub-totalling 48 marcs (including the 20 marc outer container); followed by a nominally 1 marc hollow cup which was termed the
marc creux (hollow mark); and followed by 6 further cups (4, 2, and 1
onces, and 4, 2, and 1
gros) with a final seventh filled 1
gros weight, all totalling 1 marc, which was termed the
marc plein (filled mark). Unfortunately, the weights were not consistent, with the
marc plein not being the same weight as the
marc creux, and neither being the same as a
mean 1 marc weight determined from the weight of the whole
pile. So when the time came to work out the conversion factors between these measures and the metric system, the whole
pile was taken to define 50 Parisian standard
marcs, and thus 230 400
grains (the number of grains in 50
marcs).
Louis Lefèvre‑Gineau initially determined that the metric weight of the whole
pile was 12.227 947 5 kg, later corrected to 12.2376 kg, thereby making (by division and rounded to three decimal places) a
marc 244.753 g, a
livre esterlin 367.129 g, and a
livre actuelle 489.506 g. Hence further the (Parisian)
once was 30.594 g, the
gros/
drachme was 3.824 g, the
denier/
scruple was 1.274 g, and the
grain was 0.053 g. However, the actual weights of the pre-metric measures were nowhere near even this simple. These were just the Parisian standards, and individual provinces, cities, and even guilds, all had their own reference physical standards, which were not checked against one another and which sometimes conflated
esterlin and
actuelle. For just some examples: the Marseille
livre was 399.6 g, the Montpelier one 394.9 g, the Toulon one 465.5 g, and the Toulouse one 413.2 g; with all of the fractional subdivisions having different values accordingly. The Limoges
marc was 240.929 g, the Tours one 237.869 g, and the Troyes one 250.050 g. Furthermore, there were also
livres comprising different numbers of
onces to both the
actuelle and
esterlin, including
livres of 14, 18, and 20
onces, confusing things yet further. The
livre in the
poids de table (table weight) systems used in Provence and Languedoc (and a common name for provincial weight systems in general alongside
poids de pays, country weight, and
poids de ville, town weight) was the same weight as 15
onces or even as low as 13
onces in the Parisian
poids de marc, and the
livre in the
poids de soie (silk weight) system of Lyon was similarly just the weight of the Parisian
livre. This caused an erroneous belief that these
livres comprised 13, 14, or 15
onces, however this was a confusion stemming from the equivalent
poids de marc weights, and both
poids de table and
poids de soie had 16 of their own, lighter,
onces and so forth, Rouen had a
poids de vicomté system. == See also ==