A stone, which from the description seems to have been an almost colorless variety of corundum with a faint reddish tint, is recommended in the Syrian Aristotle for the alleviation of diseases of the breast. To have the proper effect this stone was to be worn on the region affected by the malady.[263] Diamond The Hindu physicians claimed that they had found that the diamond had six flavors; it was sweet, sour, salty, pungent, bitter, and acrid. Since the stone united all these apparently contradictory qualities, we have no reason to be surprised that it should be supposed to cure all diseases and lessen all ills. An elixir of great potency, stimulating and strengthening all the bodily functions, was made from the diamond.[264] The author of the Jawâhir-nâmeh (Book of Jewels), written about a century ago, gives some of the prevalent Hindu ideas regarding the diamond. He asserts that the similarity of this stone and rock-crystal led to the belief that the latter was only an incomplete or “unripe” form of the diamond. For this reason rock-crystal was called _kacha_, “unripe,” and the diamond, _pakka_, “ripe.” The same writer, after noting the general belief that if a diamond were put in the mouth it caused the teeth to fall out, states that some were not disposed to admit this, as diamond dust had been used as a tooth-powder without any bad effects.[265] It might certainly serve to whiten the teeth, but any one who trusted to this very drastic dentifrice would soon be sadly in need of the dentist’s help. As a proof that the diamond was not much prized as an ornamental stone in the Middle Ages, although some of the praise bestowed upon it by Pliny and other classical writers was copied and recopied in a more or less perfunctory way, we may cite the few lines devoted to the stone by Psellus, who lived in Constantinople in the eleventh century A.D. This writer simply remarks of the diamond that it is hard and difficult to pierce, adding, as its chief virtue, that it would quench the heat of the “semi-tertian” fever.[266] The belief in this cooling quality of the diamond was suggested by its lack of color coupled with its extreme hardness, the latter quality being thought to augment the refrigerant power supposed to be inherent in colorless crystals which resembled ice. Emerald The emerald is especially commended for amulets to be suspended from the necks of children; it is believed to preserve them from epileptic convulsions and to prevent the falling sickness; but if the violence of the disease is such that it cannot be overcome by the stone, the latter breaks up. Bound to a woman’s thigh it is said to hasten parturition; hanging from the neck it drives off vain fears and evil spirits. It strengthens the memory, restores the sight, reveals adultery and gives a knowledge of the future, produces eloquence and increases wealth.[267]