The diamond was also believed to afford protection from plague or pestilence, and a proof of its powers in this direction was found in the fact that the plague first attacked the poorer classes, sparing the rich, who could afford to adorn themselves with diamonds. Naturally, in common with other precious stones, this brilliant gem was supposed to cure many diseases. Marbodus[473] tells us that it was even a cure for insanity. In the Babylonian Talmud we read of a marvellous precious stone belonging to Abraham. This was perhaps a diamond, or possibly a pearl; the accounts vary, and the same word is often used to designate “precious stone” and “pearl.” The following version represents it to be a diamond:[474] R. Simeon, ben Johanan said: “A diamond was hanging on Abraham’s neck, and when a sick man looked upon it he was cured. And when Abraham passed away, the Lord sealed it in the planet of the sun.” The Hindus believed that it was extremely dangerous to use diamonds of inferior quality for curative purposes, as they would not only fail to remedy the disease for which they were prescribed, but might cause lameness, jaundice, pleurisy, and even leprosy. As to the use of diamonds of good quality, very explicit directions are given. On some day regarded as auspicious for the operation, the stone was to be dipped in the juice of the _kantakára_ (_Solanum jaquiri_) and subjected for a whole night to the heat of a fire made by dried pieces of the dung of a cow or of a buffalo. In the morning it was to be immersed in cow’s urine and again subjected to fire. These processes were to be repeated for seven days, at the end of which term the diamond could be regarded as purified. After this the stone was to be buried in a paste of certain leguminous seeds mixed with asafœtida and rock salt. Herein it was to be heated twenty-one successive times, when it would be reduced to ashes. If these ashes were then dissolved in some liquid, the potion would “conduce to longevity, general development of the body, strength, energy, beauty of complexion, and happiness,” giving an adamantine strength to the limbs.[475] An Austrian nobleman, who for a long time had not been able to sleep without having terrible dreams, was immediately cured by wearing a small diamond set in gold on his arm, so that the stone came in contact with his skin.[476] The fact that in this case, as in many others, the stone was required to touch the skin, proves that the effect supposed to be produced was not altogether magical, but in the nature of a physical emanation from the stone to the body of the wearer.