It is probable that the French pound was one of the lighter pounds of the variable Northern Troy series, all with an ounce of 10 dirhems of 48 grains more or less.
The ounce was divided into 8 gros, groats or drachms, of 3 deniers or dwt., each of 24 grains. So the livre was 16 × 24 × 24 = 9216 French grains. These were light grains, not the heavy grains, 20 × 24 to the ounce, of English and other mint-weights.
There was a Quintal of 100 livres = 107·7 lb.
The Tonne or tonneau was 2000 livres = 2154 lb.
Value
The French coinage-system, probably instituted by Charlemagne, was the same as ours. The original unit was the silver penny, estelin (sterling) or denier (L. denarius) of 24 French grains; 12 deniers made a sol or sou (L. solidus, shilling) and 20 sols made the livre or pound, originally a livre d’estelins, a 12-ounce pound of sterlings. But the silver coinage shrank and was debased, until, by the eighteenth century, the pound, livre or franc was a silver coin worth tenpence, the sol a copper halfpenny, and the denier had shrunk, even as copper, to so minute a size that its place was taken by the liard, a small copper coin of 3 deniers, a quarter-sou; even the double of 2 deniers had disappeared. Accounts were kept in livres and sols and deniers, our £ s. d., but at 1/25 the present value of our coin.
The écu of 3 livres, that is of 60 sous, was largely used; wages of farm-servants are often at the present day reckoned in écus. This was properly a petit-écu or half-crown, but the real écu of 6 livres was so little used that the smaller coin took its name. And, as our half-crown has the great convenience of being one-eighth of a sovereign, so the écu had that of being one-eighth of a louis, the gold piece of 24 livres. This was the value of the louis at par, for it varied as did that of the guinea when England was a silver-standard country.
Measures of Capacity
These measures, both the wine-series and the corn-series, were quite discordant and had no relation to the measures of length. That this was caused by an incoherent system of factors is shown by there being in each series a unit derived from the perfectly concordant measures of the South:
The wine-velte = 1·76 gallon, half of the Escandau.