Histories
Herodotus
Herodotus. Godley, Alfred Denis, translator. Cambridge, MA; London: Harvard University Press; William Heinemann, Ltd., 1920-1925 (printing).
For when Cambyses marched against Egypt [30,27] (nation), Africa Egypt, he found Amasis no longer alive; he had died after reigning forty-four years, during which he had suffered no great misfortune; and being dead he was embalmed and laid in the burial-place built for him in the temple.
While his son Psammenitus was king of Egypt [30,27] (nation), Africa Egypt, the people saw an extraordinary thing, namely, rain at Thebes [32.666,25.683] (deserted settlement), Qina, Upper Egypt, Egypt, AfricaThebes of Egypt [30,27] (nation), Africa Egypt, where, as the Thebans themselves say, there had never been rain before, nor since to my lifetime; for indeed there is no rain at all in the upper parts of Egypt [30,27] (nation), Africa Egypt; but at that time a drizzle of rain fell at Thebes [32.666,25.683] (deserted settlement), Qina, Upper Egypt, Egypt, AfricaThebes .[*](In modern times there is sometimes a little rain at Thebes [32.666,25.683] (deserted settlement), Qina, Upper Egypt, Egypt, AfricaThebes ( +Luxor [32.65,25.683] (inhabited place), Qina, Upper Egypt, Egypt, Africa Luxor); very little and very seldom.)
When the Persians had crossed the waterless country and encamped near the Egyptians intending to engage them, the Egyptian mercenaries, Greeks and Carians, devised a plan to punish Phanes, angered at him for leading a foreign army into Egypt [30,27] (nation), Africa Egypt.
Phanes had left sons in Egypt [30,27] (nation), Africa Egypt; these they brought to the camp, into their father's sight, and set a great bowl between the two armies; then they brought the sons one by one and cut their throats over the bowl.
When all the sons had been slaughtered, they poured wine and water into the bowl, and the mercenaries drank this and then gave battle. The fighting was fierce, and many of both armies fell; but at last the Egyptians were routed.
I saw a strange thing on the site of the battle, of which the people of the country had told me. The bones of those killed on either side in this fight lying scattered separately (for the Persian bones lay in one place and the Egyptian in another, where the armies had first separately stood), the skulls of the Persians are so brittle that if you throw no more than a pebble it will pierce them, but the Egyptian skulls are so strong that a blow of a stone will hardly crack them.
And this, the people said (which for my own part I readily believed), is the explanation of it: the Egyptians shave their heads from childhood, and the bone thickens by exposure to the sun.