Both these dirhems became, like the drachma coin-weights of Greece, the bases of other systems of weight, either at their original weight or at the lower weights to which coins might fall.
The Lesser Rotl—
1. With its ounce of 480-1/4 grains would seem to have given rise to the Troy pounds, but it is much more probable that their variable ounces were 10 dirhems of about 48 grains.
2. From 8 of its drachms came the Venetian pound and the German apothecaries’ pound with an ounce of 8 × 57·63 = 461 grains.
From the Greater Rotl came—
1. Eight of its ounces of 450-1/4 grains = the Marc of Cologne, its double being the German Imperial pound = 7218 grains; our royal Tower-pound of Plantagenet times being 12 ounces = 5400 grains.
The 100 lb. centner of North Germany = 103·1 lb. was almost exactly the same weight as Al-Mamūn’s Cantar.
2. Weights of Eastern Europe (see [Chap. XV])
| The | Polish | pound | 16 × 8 | dirhems | of | 48·9 | grains |
| „ | Russian | „ | „ | „ | 49·37 | „ | |
| „ | Austrian | „ | „ | „ | 50·6 | „ |
From 8 dirhems of 50 to 47 grains came the ounces of the pounds of Southern France.