HISTORY OF THE STANDARDS OF WEIGHT. 
755 
use; it is mentioned in a Tractatus de Ponderibus of the same age (the time of 
Edward I.), where the two pounds are said to consist of 20 and 25 shillings respect- 
ively : in the statute of the 54th of Henry III., where the composition of the gallon 
and pound (troy ?) are given, there is mentioned also una libra, pondus vigintiquinque 
solidorum legalium sterlingorum. On many other occasions this libra mercatoria is 
referred to, and we may consider its use in mercantile transactions and ordinary sales 
as nearly universal.’ 
If the pound mentioned in the 51st and 54th of Henry III,, and the 31st of 
Edward I., be supposed to contain 5400 grains troy, the libra mercatoria will con- 
tain 6750 grains, which does not differ very much from the old pounds of Ville- 
franche (6741 '9 grains), Zieriksee (6736 grains), Dresden stahlgewicht (6726’2 
grains), Dantzig (6722 grains), Embrun (6714 grains), Murcia (6711 grains). 
This supposition is rendered probable by a passage from Fleta quoted by Clarke, 
p. 96, who says, ‘ Quindecim uncise faciunt libram mercatoriarn.’ Fifteen Tower 
ounces of 450 troy grains, twelve of which make the Tower pound, are equal to 6750 
troy grains. Sixteen of these ounces make 7200 troy grains, a weight which ap- 
proaches very closely to the Ptolemaic mina of 7199’96 troy grains, the 100th part of 
the large Alexandrian talent, also divided into 16 ounces. This weight appears to 
have survived in the old pounds of Namur (7201T grains), Altenburg (7202 grains), 
Ciney (7202*5 grains), Valenciennes (7195*2 grains), Duerstadt (7206*1 grains), Wit- 
tenberg (7207 grains), Heidelberg (7207*22 grains), Aix la Chapelle (7208 grains), 
Liege (7209*1 grains), Bruchsal (7190 grains), Brunswick (7212*3 grains), Mons 
(7185*2 grains), Dresden (7215*4 grains), Binche (7185 grains), Gotha (7213*85 
grains), Jemappe (7185*2 grains), in the well-known Cologne pound of 7216 grains, 
and in many others differing rather more largely from 7200 grains. If, on the other 
hand, the pound of Henry HI. and Edward I. contained 5760 troy grains, the libra 
mercatoria would weigh 7200 troy grains. 
In the Acts of the 2nd of Henry V. st. 2. c. 4, and of the 2nd of Henry VI. c. 13, 
relating to Goldsmiths, mention is made of the ‘Pound Troy*.’ Either the Tower 
pound was abolished, or the use of the troy pound as a legal standard confirmed in 
1498, the 12th of Henry VII. A statute made in that year enacts ‘That every 
gallon contain viii li of wheat of Troy weight and every pound xii ounces of 
Troy weight, and every ounce contain xx sterlings.’ The sterling here mentioned 
must have been a weight, and not the coin of that name ; for, during the reign of 
Henry VIL, the weight of the groat was 48 grains, and that of the shilling 144 
grains, which gives only 12 grains for the weight of the coin called the penny or 
sterling-l-. 
The troy pound appears to have been derived from the Roman weight of 5759*2 
grains, the 125th part of the large Alexandrian talent, and which, like the troy 
* Reynardson, Philosophical Transactions, vol. xlvi. p. 61. t Folkes, p. 16. 
MDCCCLVI. 5 G 
