THE UNIVERSE. OCEANIC DISCOVERIES. 247 



analytical chemistry. His hopes were indeed directed to 

 the transmutation of metals ; but in seeking the fulfilment 

 of these hopes, he not only materially improved the practical 

 manipulation and treatment of ores, brit also gained additional 

 insight into the general mode of operation of the chemical 

 forces of nature. His works contain some exceedingly acute 

 detached remarks on the organic structure and physiology 

 of plants. He was acquainted with the sleep of plants, 

 with the periodical opening and closing of blossoms, with 

 the diminution of sap during evaporation from the cuticle 

 of the leaves, and with the influence of the distribution 

 of the bundles of vessels on the indentations of the leaves. 

 He wrote a commentary upon, the whole of Aristotle's works 

 on physics and natural history, following, however, in the 

 history of animals, only the Latin translation of Michael 

 Scot from the Arabic ( 381 ) A work of Albertus Magnus 

 bearing the title of Liber Cosmographicus de Natura 

 Locorum is a species of physical geography. I have 

 found in it considerations on the dependence of tempera- 

 ture concurrently on latitude and elevation, and on the effect 

 of different angles of incidence of the sun's rays in heating 

 the ground, which have excited my surprise. He owes 

 perhaps his having been celebrated by Dante, less to himself 

 than to his beloved scholar Thomas Aquinas, who he took 

 with him from Cologne to Paris in 124*5, and brought back 

 to Germany in 1248. 



Questi, cite m' e a destra piu vicino, 

 Frate e maestro fummi ; ed esso Alberto 

 E' di Cologna, ed io Thomas d' Aquino. 



IL PARADISO, x. 97 99. 



In all that relates immediately to the extension of the 



