| 3 gendum dsho (barley-corn) | = | 1 nashod. |
| 4 nashod (a kind of pea, lupin?) | = | 1 dung. |
| 6 dung | = | 1 miscal[234]. |
Although the miscal and habba denote Arabic influence, we may, without straining probabilities, conjecture that the use of the barley-corn here as well as in India, where we found it at a period anterior to Muhammadan conquest, indicates that in Persia it existed likewise from the earliest times. The close relationship between the ancient Hindus and ancient Persians makes it all the more likely. It is also pointed out that formerly the nashod was divided into three instead of four grains. As the Arabs divide their karat into four habbas, it is all the more likely that the 3 barley-corns = 1 nashod belong to the ancient system.
The Arab weight system is based on the grain of wheat, four of which make a karat (the seed of the carob or St John’s Bread)[235]. Occasionally in the Arab writers mention is made of a karat divided into 3 habbas[235]. The weight of the karat remains unchanged, but the grains in this case are barley grains, since, as we shall see presently, 3 grains of barley are equal to 4 grains of wheat (·063 × 3 = ·047 × 4).
It will now be most convenient for us to begin in the extreme west, and once more from that work back towards the coast of the Aegean Sea, in which our chief interest must always be centred.
Whether the Kelts of Ireland had any indigenous weight system or not, we have no direct evidence, although we do know as a fact that when Caesar landed in Kent he found the Britons employing coins of gold and bronze, and bars (or according to some MSS. rings) of iron adjusted to a fixed weight. However the earliest Irish documents reveal that people using a system of weights for silver directly borrowed from the older Roman system (although it is likely that they had a native standard for gold). As the solidus and denarius became the chief units of Europe from the time of Constantine the Great (336 A.D.), the Irish probably received their system at an earlier date.
| 1 unga (uncia) | = | 24 screapalls (scripula). |
| 1 screapall | = | 3 pingiuns. |
| 1 pingiun | = | 8 grains of wheat[236]. |
When we pass to England, the very word grain which we employ to express our lowest weight unit, would of itself suggest that originally some kind of grain or seed was employed by our forefathers in weighing, but as the grain in use among us is the grain Troy, and as we have not yet learned its origin, it will not do to argue vaguely from etymology. But a little enquiry soon brings us to a time when the grain Troy did not as yet form the basis of English weights, and when a far simpler method of fixing the weight of the kings coinage was in vogue. It was ordained by 12 Henry VII. ch. V. “that the bushel is to contain eight gallons of wheat, and every gallon eight pounds of wheat, and every pound twelve ounces of Troy weight, and every ounce twenty sterlings, and every sterling to be of the weight of thirty-two grains of wheat that grew in the midst of the ear of wheat according to the old laws of this land[237].” Going backwards we find that in 1280 (8 Edward I.) the penny was to weigh 24 grains, which by weight then appointed were as much as the former 32 grains of wheat. By the Statute De Ponderibus, of uncertain date but put by some in 1265, it was ordained that the penny sterling should weigh 32 grains of wheat, round and dry, and taken from the midst of the ear. Going back a step still further we find that by the Laws of Ethelred, every penny weighed 32 grains of wheat[238], and as the pennies struck by King Alfred weigh 24 grains Troy, we may assume without hesitation that they were struck on the same standard of 32 grains of wheat. Thus from Alfred (871-901) down to Henry VII. (1485-1509), we find the penny fixed by this primitive method, and the actual weight of the coins, as tested by the balance at the present day, affords proof positive of the method.
But all the standards of mediaeval Europe (with the exception of the Irish) were based on the gold solidus of Constantine the Great[239]. The solidus (itself weighing 72 grains Troy or ⅟₇₂ of the Roman pound) was divided into 24 siliquae. The siliqua, or as the Greeks called it keration (κεράτιον, from which comes our word carat), was the seed of the carob, or as it is often called, St John’s Bread (Ceratonia siliqua L). Thus the lowest unit in the Roman system, as it is usually given, is found to be the seed of a plant. The same holds of the Greek system, for the drachma is described as containing 18 kerata or keratia, whilst according to others “it contains three grammata, but the gramma contains two obols and the obol contains three kerata, and the keras contains four wheat grains[240].” From this we see that the keration or siliqua was further reduced to 4 sitaria, or grains of wheat, whilst from another ancient table of weights[241] we learn that the siliqua likewise equals 3 barley-corns (siliqua grana ordei iii). Hence it appears that 3 barley-corns = 4 wheat grains. Thus both Greek and Roman systems just like the English and Irish take as their smallest unit a grain of corn. This also throws important light on the origin of that mysterious thing, the Troy grain. We saw above (8 Edward I.) that at the time of its introduction into England that 24 grains Troy = 32 grains of wheat, that is the Troy grain stands to wheat grain as 3:4. But as we have just seen that the siliqua = 3 barley-corns, and also = 4 wheat-corns, it follows that 3 barley-corns = 4 wheat-corns. And as 3 Troy grains = 4 wheat-corns, it likewise follows that 3 Troy grains = 3 barley-corns, or in other words, the barley-corn and Troy grain are the same things. It thus appears that the Troy grain is nothing more than the barley-corn, which was used as the weight unit in preference to the grain of wheat in some parts of the Roman empire. Furthermore this relation between barley-corns and wheat-corns can be proved to be a fact of Nature. In September, 1887, I placed in the opposite scales of a balance 32 grains of wheat “dry and taken from the midst of the ear,” and 24 grains of barley taken from ricks of corn grown in the same field at Fen Ditton, near Cambridge, and I thrice repeated the experiment; each time they balanced so evenly that a half grain weight turned the scale. The grain of Scotch wheat weighs ·047 gram, the Troy grain = ·064, ·047 × 4 = 188, ·064 × 3 = 192. Practically 4 wheat grains = 3 Troy grains.
Before passing from the Greek and Roman standards I may add that even higher denominations than the siliqua were expressed by the seeds of plants. The Romans made the lupin (lupinus) = 2 siliquae and under its Greek name of thermos (θερμός), it was assigned a like value (Metrol. Script. I. 81). In the Carmen de Ponderibus (Metrol. Script. II. 16), 6 grains of pulse (grana lentis) are made equal to 6 siliquae, and a like number of grains of spelt are given a similar value.
We next advance towards the East and take up the Semitic systems. We have already had occasion to touch upon that of the Arabs when dealing with the modern Persians. “There can be little doubt,” says Queipo (I. 360), “that the Arab system of weight was based on the grain of wheat.” The habba was their smallest unit. Four habbas are equal to 1 karat, the latter of course representing the keration or siliqua, and the former the 4 sitaria or wheat-grains, which we saw were its equivalent. This is the most ordinary value given to the karat in Makrizi and the other Arabic writers on Metrology, but occasionally we find the karat made equal to only 3 grains, which of course are barley-corns. We saw above that in the Persian system the nashod was formerly divided into 4 habbi of ·048 gram (which is plainly the weight of the wheat-grain), whilst now it is divided into 3 grains each of ·063 which represents the barley-corn, or in other words the Troy grain of ·064 gram. Of course the objection might be raised that as the Arabs had borrowed their higher denominations such as the dirhem (δραχμή) and dinar (denarius, δηνάριον), from the Greeks and Romans, and as their standard weight the mithkal is nothing more than the sextula or ⅙ of the Roman ounce, employed in the eastern Empire under the name of exagion (ἐξάγιον, whence comes the saggio of Marco Polo), so too their wheat-corns and barley-corns were not of their own devising, but likewise adventitious. After what we have seen above ([p. 166]) to be the practice of primitive people in the selling of gold, a traffic in which the Arabs had been engaged for many ages, it would seem hardly necessary to reply to such an argument, but as a more complete answer can be given in the course of the last portion of this enquiry, we shall deal with it in that place.