Hymettus was also famous in antiquity for its marble, which seems to have been especially prized by the Romans. This marble, which is still quarried in large quantities on Hymettus, is a bluish-grey streaky marble, of finer and closer grain than the white Pentelic marble, but far inferior to it in beauty. The Greeks seem not to have used it commonly till the third century B.C. From that time onward we find it employed for tombstones, inscriptions, and the casing of buildings. The principal quarries are on the western side of the mountain, on the slopes which enclose the valley of St. George on the south and south-east and which on the other side descend nearly sheer into ‘the Devil’s Glen’ or ‘the Evil Glen,’ the deepest and wildest gorge in Hymettus. Vestiges of the ancient road or slide by which the blocks were brought down from the quarries may be seen about a hundred yards above the chapel of St. George; the road seems to have been led in serpentine curves down the slope, not in a straight line like the road from the quarries on Pentelicus. A great part of the upper ridge of Hymettus is composed of a white marble resembling the white marble of Pentelicus, but inferior to it in crystalline structure and of a duller white. The ancients apparently made little use of this white Hymettian marble. Clouds on Hymettus were believed to prognosticate rain; if during a storm a long bank of clouds was seen lowering on the mountain, it meant that the storm would increase in fury. Hymettus is still as of old remarkable for the wonderful purple glow which comes over it as seen from Athens by evening light. When the sun is setting, a rosy flush spreads over the whole mountain, which, as the daylight fades and the shadows creep up the slope, passes by insensible transitions through all intermediate shades of colour into the deepest violet. This purple tinge is peculiar to Hymettus; none of the other mountains which encircle the plain of Athens assumes it at any hour of the day. It was when the sunset glow was on Hymettus that Socrates drained the poisoned cup. VII. MOUNT PENTELICUS.—Pentelicus is the pyramid-like mountain, between three and four thousand feet high, which closes the Athenian plain on the north-east, at a distance of about ten miles from Athens. Its upper slopes, as seen from the Acropolis at Athens, have been aptly compared to the pediment or gable of a Greek temple. Through the clear air of Attica the unaided eye, looking from the Acropolis, can distinguish the white line of the ancient quarries descending, somewhat to the right of the highest peak, straight down into the valley where the monastery of Mendeli lies hidden by the intervening heights; to the left of the summit, half-way up the slope, may be discerned the large white patches which mark the site of the modern quarries.