In sailing from Heroopolis along Troglodytica, a city is met with called Philotera,[710] after the sister of the second Ptolemy; it was founded by Satyrus, who was sent to explore the hunting-ground for the elephants, and Troglodytica itself. Next to this is another city, Arsinoë; and next to this, springs of hot water, which are salt and bitter; they are precipitated from a high rock, and discharge themselves into the sea. There is in a plain near (these springs) a mountain, which is of a red colour like minium. Next is Myus Hormus, which is also called Aphrodites Hormus;[711] it is a large harbour with an oblique entrance. In front are three islands; two are covered with olive trees, and one (the third) is less shaded with trees, and abounds with guinea-fowls.[712] Then follows Acathartus (or Foul Bay), which, like Myus Hormus, is in the latitude of the Thebaïs. The bay is really foul, for it is very dangerous from rocks (some of which are covered by the sea, others rise to the surface), as also from almost constant and furious tempests. At the bottom of the bay is situated the city Berenice.[713] 6. After the bay is the island Ophiodes,[714] so called from the accidental circumstance [of its having once been infested with serpents]. It was cleared of the serpents by the king,[715] on account of the destruction occasioned by those noxious animals to the persons who frequented the island, and on account of the topazes found there. The topaz is a transparent stone, sparkling with a golden lustre, which however is not easy to be distinguished in the day-time, on account of the brightness of the surrounding light, but at night the stones are visible to those who collect them. The collectors place a vessel over the spot [where the topazes are seen] as a mark, and dig them up in the day. A body of men was appointed and maintained by the kings of Egypt to guard the place [CAS. 770] where these stones were found, and to superintend the collection of them. 7. Next after this island follow many tribes of Ichthyophagi and of Nomades; then succeeds the harbour of the goddess Soteira (the Preserver), which had its name from the circumstance of the escape and preservation of some masters [of vessels] from great dangers by sea. After this the coast and the gulf seem to undergo a great change: for the voyage along the coast is no longer among rocks, and approaches almost close to Arabia; the sea is so shallow as to be scarcely of the depth of two orguiæ,[716] and has the appearance of a meadow, in consequence of the sea-weeds, which abound in the passage, being visible through and under the water. Even trees here grow from under the water, and the sea abounds with sea-dogs.