hypothesis impossible by showing that all the diobols yet known are probably later than the time of Aristotle[432]. As, however, this rests on negative evidence, and is liable to be overthrown at any moment by the discovery of an archaic diobol, it is advisable to cast about for some more positive criterion. Heraclea of Lucania, the daughter-city and close neighbor of Tarentum, as we know from the famous Heraclean Tables (which scholars are agreed in regarding as written about the end of the 4th cent. B.C.), employed as a unit of account a silver _nomos_. It is so probable that the _nomos_ employed at Heraclea (_circ._ 325 B.C.) would be the same in value as that employed at Tarentum in the time of Aristotle (_ob._ 322 B.C.), that if we can prove the _nomos_ of Heraclea to be a _didrachm_ and not a _diobol_, we may henceforth hold with certainty that the _nomos_ of Tarentum was the larger coin. On the Heraclean Tables it is enacted that those who held certain public land should pay certain fines in case they had failed to plant their holdings properly; four olive trees were to be planted on each _schoenus_ of land, and for each olive tree not so planted a penalty of 10 _nomi_ of silver was to be exacted, and for each _schoenus_ of land not planted with vines the penalty was two _minae_ of silver[433]. The _schoenus_ is identical with the Roman _actus_ (half a _jugerum_), being the square of 120 feet. Four olive trees were the allowance for each _schoenus_. Now if we can determine the number of vines which were planted on a _schoenus_, we shall be able to get a test of the value of a _nomos_. Two minae of silver contained in round numbers 110 Tarentine didrachms of 123 grs. each, or 675 diobols of about 20 grs. each. Olives were many times more valuable than the vine, so that any result which will make the vine about the same value as the obol will be absurd. Now Mr A. J. Evans, when in Southern Italy, at my request kindly ascertained that vines, when trained on poles on vineyard slopes, are usually about 3 yards apart, whilst when trained on pollard poplars (as is much more usual in Campagna), they stand about 6 yards apart. In the case of the former about 150 vines would go to a _schoenus_ (1600 sq. yards), whilst in the latter case barely 50. We cannot doubt that the distance between the vines must have been much the same in ancient as in modern times.