CHEMICAL LITERATURE. 435 



the Arabians has left a deep impression on chemical science. Cultivated chiefly 

 by physicians, attention was directed to its pharmaceutical applications, and in 

 spite of the prohibitions of the Koran, to the fascinations of alchemy. Of their 

 extant writings, preserved in European libraries, only a portion have been edit- 

 ed ; those best known partake of the poetical imagery and hyperbole characteris- 

 tic of the Oriental mind. This is shown to some extent in the singular titles pre- 

 fixed to their treatises, e.g., "The Rise of the Moon under the Auspices of 

 Golden Particles," by the alchemist Dschildegi ; " A Poem in the Praise of God, 

 of Mahomet and of Alchemy," by Dul-nun-el-Misri. 



The well known treatises of Geber, "Of the Investigation of Perfection," 

 " Of the Sum of Perfection," " Of the Invention of Verity," and " Of Furnaces," 

 notwithstanding a bewildering style of composition, which seems to confirm Dr. 

 Johnson's derivation of gibberish, from Geber, display very great familiarity with 

 a large number of chemical substances and operations. 



Geber's works are generally assigned to the eighth century and consist chiefly 

 of compilations from the " Books of the Ancients; " he mentions no author by, 

 name. They contain chapters devoted to the seven known metals, to the methods 

 of distillation, calcination, cupellation and other operations, to the preparation of 

 saline substances and to chemical philosophy. Geber adopted Aristotle's views 

 of the constitution of matter from four principles, the hot and cold, the wet and 

 dry, and adds thereto : " Mercury and sulphur are the components of metals," 

 a doctrine which with slight modifications prevailed for more than eight centuries. 

 Geber describes the preparation of nitric acid, of aqua regia, and of mercuric 

 oxide ; he mentions the increase in weight of metals when calcined with sulphur, 

 and gives the results of a rude quantitative analysis of crude sulphur. He con- 

 stantly maintains the doctrine of transmutation of metals and gives a refutation 

 of the ingenious arguments opposed thereto. His remarks on the qualifications 

 of a chemist are most intelligent and are not inopportune in modern times; he 

 urges the necessity of diligence, patience, learning, a temperate disposition, 

 slowness to anger, and a full purse, "for this science agrees not well with a man 

 poor and indigent," together with faith in the God who "withholds or gives to 

 whom he will" the secrets of nature, and who will infalUbly punish the foolish 

 meddler with magical mysteries. 



To detail fuUy our obligations to Arabian chemists is no part of our plan. 

 They have left an indelible impression on the very language of the science, in the 

 words alcohol, alembic, alkali, borax, and many others. All honor to the intel- 

 ligent authors who a thousand years ago defined chemistry as the " Science of 

 Combustion, the Science of Weight, the Science of the Balance 1 " 



In the midd'e ages intellectual activity was confined largely to the clergy, 

 who controlled the schools of learning, the libraries, and nearly all sources of knowl- 

 edge. University chairs were occupied exclusively by clerical professors, literature 

 and science were cast in ecclesiastical moulds. Scientific treatises were the produc- 

 tion of monks and emanated from cloisters. Many distinguished philosophers 

 mastered widely separated branches of learning : among these were Alain de 



