PROGRESS AMONG THE ARABS. 41 



science in every direction. They undertook remote travels 

 and explorations with the view to enrich and diffuse the 

 knowledge of geography, botany, natural history, mineralogy. 

 For instance : 



720. Assamsh, as early as 720, created scientific TOPO- 

 GRAPHY and statistics. 



1130. Artefius, in his "Key to Wisdom," defined the 

 nature of MINERALS, plants, and animals with as much 

 lucidity and terseness as Linnaeus. " Minerals," he says, 

 " derive from the elements, plants from the minerals, animals 

 from plants." He described the preparation of soap. 



116231. Abdallatif, the favourite of Saladin, described 

 the ANIMALS AND PLANTS OF EGYPT with an accuracy 

 unknown before him. The hippopotamus is described by 

 him better than by Hercdotus, Aristotle, and Pliny. He 

 rectified Galenus as to the human osteology. Had the Nile 

 mud dug to discover the antiquity of Egyptian civilisation 

 to a depth of 43 feet, counting 13,500 yearly mud layers, and 

 finding pottery at that depth. 



Xllth (?). Abn Othman added new facts to the know- 

 ledge of ZOOLOGY, too numerous to describe in detail. 



1248. Al Beithar did the same for BOTANY. After ex- 

 tensive travels, he composed a General History of Plants 

 alphabetically planned, in which he speaks of many species 

 unknown before, and also of their medical properties. 



950. Al Farabi had nearly three hundred years before de- 

 tected the RESPIRATION OF PLANTS, in the leaves and bark. 



Xllth (?). Alberuni extended the knowledge of mine- 

 ralogy, and of PRECIOUS STONES especially. 



1130. Al Idrisi increased the knowledge of geography; 

 he made a silver GLOBE for King Roger II. of Sicily. 



1283. Karwiny's "Wonders of Nature' 3 embraces as- 

 tronomy, geography, natural history ; treats of meteors and 

 other atmospheric phenomena. He ascribed EARTHQUAKES- 

 to vapours which act in the interior of the earth as in a vast 

 laboratory ; described two kinds of elementary vapours : 



I. those above the earth which form clouds, rain, snow; 



II. those under the earth which cause earthquakes. He also 

 speaks of the displacement of the sea. " A place," he says. 



