[Illustration:  047.jpg an Arab girl]

The Romans in most cases collected the revenues of a province by means of a publican or farmer, to whom the taxes were let by auction; but such was the importance of Egypt that the same jealousy which made them think its government too great to be trusted to a man of high rank, made them think its revenues too large to be trusted to one farmer.  The smaller branches of the Egyptian revenue were, however, let out as usual, and even the collection of the customs of the whole of the Red Sea was not thought too much to trust to one citizen.  Annius Plocamus, who farmed them in this reign, had a little fleet under his command to collect them with; and, tempted either by trade or plunder, his ships were sometimes as far out as the south coast of Arabia.  On one occasion one of his freedmen in the command of a vessel was carried by a north wind into the open ocean, and after being fifteen days at sea found himself on the coast of Ceylon.  This island was not then wholly new to the geographers of Egypt and Europe.  It had been heard of by the pilots in the voyage of Alexander the Great; Eratosthenes had given it a place in his map; and it had often been reached from Africa by the sailors of the Red Sea in wickerwork boats made of papyrus; but this was the first time it had been visited by a European.

In the neighbourhood of the above-mentioned road from Koptos to Berenice were the porphyritic quarries and the emerald mines, which were briskly worked under the Emperor Claudius.  The mountain was now named the Claudian Mountain.

As this route for trade became known, the geographers began to understand the wide space that separates India from Africa.  Hitherto, notwithstanding a few voyages of discovery, it had been the common opinion that Persia was in the neighbourhood of Ethiopia.  The Greeks had thought that the Nile rose in India, in opposition to the Jews, who said that it was the river Gibon of the garden of Eden, which made a circuit round the whole of the land of Cush, or Ethiopia.  The names of these countries got misused accordingly; and even after the mistake was cleared up we sometimes find Ethiopia called India.

The Egyptian chemists were able to produce very bright dyes by methods then unknown to Greece or Rome.  They dipped the cloth first into a liquid of one colour, called a mordant, to prepare it, and then into a liquid of a second colour; and it came out dyed of a third colour, unlike either of the former.  The ink with which they wrote the name of a deceased person on the mummy-cloth, like our own marking-ink, was made with nitrate of silver.  Their knowledge of chemistry was far greater than that of their neighbours, and the science is even now named from the country of its birth.  The later Arabs called it Alchemia, the Egyptian art, and hence our words alchemy and chemistry.  So also Naphtha, or rock oil, from the coast of the Red Sea; and Anthracite, or