A History of Agriculture in India v2.c53.s7.4

v2.c53.s7.4

With the aid of new instruments of observation, the Arab philosophers acquired the exact knowledge of the circumference of the earth, and the position and the number of planets. Astronomy began to outgrow its primitive form (divinations of astrology), and developed into an exact science. Although algebra had been invented by Diophantus of Alexandria, it did not become an object of common study until the age of Arabic learning. Botany was studied for medical purposes; yet the discovery of two thousand varieties of plants by Dioscorides represented the birth of a new science. Chemistry owes its origin and initial development to the industry of the Arabs. The most renowned of the alchemists was Jabir ibn Hayyan (fl. about A.D. 800), and Al-Razi (about A.D. 865-925), also known as Rhazes. The Arab alchemists discovered new substances, such as potash, nitrate of silver, and nitric and sulphuric acids. The word alcohol is Arabic.