3. The Mediterranean Systems of Weight
In Egypt the dirhem-system gives rise to two series of weights: that of the Oka and that of the Rottolo. In the latter word the Arabic ‘rotl’ is Italianised, the Arabic weights having come under Roman influence; an influence of long standing, since Al-Mamūn divided the Cantar after the Roman plan into 125 lesser rotl as well as into 100 greater rotl, when the Arabic gold Mithkal, 1/72 of the Egypto-Roman libra, took the place of the exagium solidi or aureus, 1/72 of the Roman mint-As.
The Mithkal, or Miskal, = 72·74 grains, was divided into 24 Egyptian qirát = 3·03 grains, as the Aureus had been divided into 24 Roman Siliquæ = 2·92 grains, and 16 of the 24 qirát was the standard of the silver dirhem = 48·5 grains, the lesser dirhem.
The golden Dinar, 21-3/4 qirát, was of the weight of the Attic commercial drachma = 65·6 grains; it displaced the Roman golden denarius. But the lesser dirhem, 2/3 the weight of the Mithkal, did not succeed in displacing an old-established drachma, which became a greater dirhem. For, as the Mithkal had a dirhem 2/3 of its weight, so the Roman Aureus, 1/6 of the As-ounce, had a silver drachma 3/4 of its weight. The As, originally 1/100 of the Greek-Asiatic talent, had its ounce divided, after the Greek system, into 8 drachmæ each 5049/(12 × 8) = 52·6 grains. Apparently this greater dirhem tended, in Arab times, to fall towards the standard of the lesser dirhem = 48·5 grains. This is the probable explanation of the variations of the dirhems, and of the pounds based on them, along the Mediterranean coasts.
In Tunis the dirhem = 48·58, almost exactly the original weight of the lesser dirhem. But in Tripoli there are two standards, 47·075 and 50·1 grains. The Ukyé or ounce is goldsmith’s weight, 10 dirhems of 47·075 grains; but in commercial weight it is in dirhems of 50·1 grains, so it is made the same weight by reckoning it as 150 kharūb or qirát instead of 160 of these as in the goldsmith’s ounce of 10 dirhems of 16 qirát.
So there are variations in the weight of the dirhem basis of the Mediterranean pounds:
| In Egypt the | dirhem | = | 47·66 | grains |
| In Tripoli | „ | = | ⎧47·07 | „ |
| ⎩50·1 | „ | |||
| In Tunis | „ | = | 48·58 | „ |
| In Morocco | „ | = | 49 | „ |
| In Turkey | „ | = | 49·6 | „ |
The qirát, 1/16 of the dirhem, varies with it.
Egypt
The Oka, = 2·723 lb., is 400 dirhems of 47·66 grs.
The Rottolo, = 98 lb., is 144 dirhems of 47·66 grs.
The Oka is a centesimal multiple of the dirhem.
The Rottolo is an uncial multiple of it.
100 Rottoli = 1 Cantar = 98 lb.; this is the modern Egyptian Cwt. which has succeeded the Cantar of Al-Mamūn = 102·92 lb.
Turkey
There is a double series as in Egypt, but the Turkish series are based, one on the Dirhem and the other on the Egypto-Roman ounce at the standard of 436·45 grains. In modern Rome it is 436·26 grains, in Tuscany 436·66 grains.
The Dirhem, = 49·5 grains, is 16 qirát of 3·1 grains.
The Cheké is of 100 dirhems = 4950 grains.
The Oka is of 400 dirhems = 2·83 lb.
The Cantar is = 2000 ounces = 124·7 or 44 Oke.
The Cantar is divided into 100 Rottoli of 1·247 lb., = 20 ounces.
The Libbra and the Rottolo
Rottoli of over 16 ounces are not uncommon in Mediterranean countries, whether Moslem or Christian. They form an alternate series with the libbra series. Thus in Algiers there are 3 rottoli of 16, 18 and 24 oz., each ounce, = 526·6 grains, being 10 greater dirhems, and coinciding with the Russian ounce. There are—
in Sicily a 12-oz. libbra, = 4897 grs., and a 30-oz. rottolo = 12,244 grs.;
in Malta a 12-oz. libbra, = 4886 grs., and a 30-oz. rottolo = 12,215 grs.;
in Genoa a 12-oz. libbra, = 4893 grs., and an 18-oz. rottolo = 7378 grs.;
in Naples a 12-oz. libbra, = 4950 grs., and a rottolo = 13,750 grs.
These Italian libbre belong to the dirhem system, their ounces being 8 dirhems of slightly different weights; and the ounces are of much lower weight than the ounces of the northern countries or of ancient Rome. Though divided into 12 ounces, these libbre belong to the same class as the 16-oz. pounds of Southern France; all having ounces of 8 dirhems. But in North Africa the Oka and the rottolo have an ounce of 10 dirhems.
Ounces and Dirhems of the Mediterranean System
| Lb. | of | Oz. | Dirhem of | ||||||
| Genoa | 12 oz. | 408·5 | grs. | 1/8 | = 51 | grs. | |||
| Sicily | „ | 408 | „ | 1/8 | = 51 | „ | |||
| Malta | „ | 407 | „ | 1/8 | = 51 | „ | |||
| Sardinia | „ | 392·6 | „ | 1/8 | = 49·1 | „ | |||
| Majorca | „ | 392 | „ | 1/8 | = 49 | „ | |||
| Languedoc | 16 oz. | 400 | „ | 1/8 | = 50 | „ | |||
| Gascony | „ | 392 | „ | 1/8 | = 49 | „ | |||
| Provence | „ | 377 | „ | 1/8 | = 47·1 | „ | |||
| Turkey | = 49·5 | „ | |||||||
| Egypt | = 47·66 | „ | |||||||
| Morocco | Rotl | 20 oz. | 392 | „ | = 49 | „ | |||
| Tripoli | Oka | 40 oz.⎫ | 470·75 | „ | 1/10 | = 47 | „ | ||
| Algiers | Rotl | 16 oz.⎭ | |||||||
| Tunis | Rotl | 16 oz. | 485·8 | „ | 1/10 | = 48·58 | „ | ||
Everywhere there is a Cantar or Quintal, a hundredweight, divided into 4 rūba and into 100 pounds or rotl.
In Tunis the Cantar = 111 lb., divided into 100 rotl of 16 ukyé or ounces of 10 dirhems.
In Tripoli it is = 107·6 lb., in 100 rotl of 16 ukyé, of 8 dirhems of 47·075 grains.
In Morocco it is = 112 lb. of 100 rotl, each of 20 ukyé of 8 dirhems; the ukyé or ounce = 392 grains as in Gascony (Foix, Albi, &c.), where it was 8 ternau.
SUMMARY
However differently the Mediterranean pound or the rotl may be divided, its ukyé or ounce is always based on one of the dirhems. This dirhem-basis is found in every pound used in Europe and the countries colonised from Europe.
The pound, whether of 12 or 16 ounces, found in Morocco, Majorca, Sardinia, Gascony, is then an Arabic weight, with an ounce of 8 dirhems, of 49 grains = 392 grains.
The pound of Provence was 16 ounces, each 8 dirhems of 47·1 grains.
The Troy pounds had ounces of 10 dirhems varying between 47·2 grains for French Troy and 48·3 for northern Troy.
The Spanish pound = 7101 grains, its ounce = 443·8 grains, was originally at the Moorish standard of 6 mithkals to the ounce, that is the Egypto-Roman ounce, the old averdepois ounce. But 6 mithkals being equal to 9 lesser dirhems, this dirhem-basis appears to have been taken. Then, for lesser dirhems of 48·5 grains, 9 heavier dirhems of 49·3 grains, nearly the Morocco and Gascony standard, were substituted.
The Nuremburg or Venetian pound. Its ounce, = 460 grains, was 12 drachms of 57·6 grains, 1/100 of the lesser rotl.
The Cologne pound of 7200 grains, its ounce = 451 grains, or at Tower standard 450 grains, was the greater rotl. Or its ounce was 9 dirhems of that rotl, dirhems of 50·03 grains.
It is thus seen that every European pound is composed of ounces on a dirhem-basis, of 8, 9, 10 or 12 dirhems; or, as in the case of the averdepois ounce, coinciding with the ounce of 6 mithkals or 9 dirhems. The ounce was—
8 dirhems in the light Mediterranean pounds.
9 dirhems in the medium pounds of Spain and Cologne.
10 dirhems in the Troy pounds.
10 greater dirhems in the Russian pound.
12 drachmæ in the Venetian pound.
Original Weights of the Dirhems
| 1. | Coin-weights:— | Grains. | ||||||
| Aureus, | 1/6 | of | As-ounce | 70·1 | ||||
| 3/4 | „ | 1/8 | „ | „ | greater dirhem | 52·6 | ||
| Mithkal, | 1/6 | of | Egypto-Roman ounce | 72·74 | ||||
| 3/4 | „ | 1/9 | „ | „ | „ | lesser dirhem | 48·5 | |
| 2. | Rotl-weights:— | |||||||
| 1/100 lesser rotl | drachma | 57·63 | ||||||
| 1/144 greater rotl | medium dirhem | 50·03 | ||||||