THE SOURCE OF THE NILE. 687
in common ufe, and this, too, I conceive to be Strabo's mean- ing. But let us compute from Herodotus, who fays that 16, or at lead 15, were neceffary in his time, whilft Strabo informs us, that, before Petronms exerted himfelf as to the banks and califiies juft mentioned, the extreme abundance mufl then have been at 12, and the minimum at 10. Now,, by this paffage, beyond all exception, it is clear that there could have been no increafe indicated by the Nilometer; for 10 cubits watered the whole land of Egypt fufficiently in Stra- bo's time, whereas 16 and 15 were neceflary in the days of Herodotus: and I muft likewife obferve* that if we mould fuppofe the fame induftry and attention ufed in Mxris's time that was in Petronius's, (and there is every reafon to induce us to think there was) then the proof is pofitive, that there was no difference in the foil of Egypt indicated by the Ni- lometer for thefirft 1400 years.
From this let us defcend to Hadrian, about 100 years after- wards. We know from Pliny*, and from an infenpdon upon a medal of great brafs of Hadrian's, who was himfelf in Egypt, that 16 cubits were then the fifcal term or rife of the Nile, by which the Egyptians paid their rent ; and this is precifely what Herodotus fays, in his time, was no more than fufficient.
Aboi;t the beginning of the 4th century, in the emperor Julian's reignf, 15 cubits were a fufficient minimum to in- cur the payment of the tribute, and this is one of the terms
v ' iH - 4 * that
- Plin. Jib. xxxvi. cap. *r. PhHoft. d: Icon. Nili.
t Julian. Epift. egdicio prefeflo Egypti.
