"Chemistry developed from two sources—medicine and industry. Something has been said about the chemical excellence of cast iron in ancient India, and about the high industrial development of Gupta times, when India was looked to, even by Imperial Rome, as the most skilled of the nations in such chemical industries as dyeing, tanning, soap-making, glass and cement. As early as the second century B.C. Nagarjuna devoted an entire volume to mercury. By the sixth century the Hindus were far ahead of Europe in industrial chemistry; they were masters of calcination, distillation, sublimation, steaming, fixation, the production of light without heat, the mixing of anesthetic and soporific powders, and the preparation of metallic salts, compounds and alloys. The tempering of steel was brought in ancient India to a perfection unknown in Europe till our own times; King Porus is said to have selected, as a specially valuable gift for Alexander, not gold or silver, but thirty pounds of steel.22 The Moslems took much of this Hindu chemical science and industry to the Near East and Europe; the secret of manufacturing “Damascus” blades, for example, was taken by the Arabs from the Persians, and by the Persians from India."