IV 



Ural, the Altai, and the Caspian Sea and the boundary of China. This 

 journey laid the foundation of the knowledge of the Mineralogy of the 

 extensive Eussian Empire. His researches in Germany were devoted to 

 the Silesian mountains. 



Gr. Eose was the first in his own country who determined accurately the 

 angles of crystals with the aid of the reflecting goniometer. He took an 

 important part in the labours which led Mitscherlich to the discovery of 

 isomorphism. His labours embrace every department of Mineralogy — 

 crystalline forms and their combinations, the physics of crystallography, 

 the chemical composition and the artificial production of minerals, and 

 the art of crystallographic drawing. The knowledge of the association 

 of minerals in rocks (petrography) was founded by him, as he was one 

 of the first who taught how, with the aid of the microscope, to investigate 

 the minerals invisible to the eye in a very thin polished plate of stone. 



He applied himself with especial delight to the study of Meteorites, 

 those wonderful bodies which fall on the earth out of the depths of space. 

 The structure of the iron meteorites, the mineralogical constitution of 

 the stony meteorites revealed themselves to his acute research. His mind 

 busied itself perpetually with the extraordinary difference between the 

 formation of the stony matter in those cosmic masses and in the solid 

 crust of the earth. It is truly remarkable that his most beautiful 

 mineralogical discoveries were not made in operating upon rare minerals, 

 but upon such as exist in all collections, and of which many have been ex- 

 posed to observation before. To these belong the distinctions of the forms 

 of quartz and its various twins; the crystallization of pyrites, sought after 

 by many in vain. The secret of making such discoveries consisted in 

 this, that he never sought after the form alone, but always contem- 

 plated the totality of the physical appearances. During the last year of 

 his life his inquiring thoughts were especially directed to the diamond. 

 Eew mineralogists are capable of conjecturing that the diamond in its 

 form yet exhibits perplexities. So occupied was he with this problem, 

 that he dictated to one of his sons the results of this last intellectual 

 labour only four-and-twenty hours before his end. 



He saw his best friends and truest companions of his labours, Mit- 

 scherlich, Magnus, Haidinger, and above all his brother Heinrich, called 

 away from their work. Their departure and his increasing solitude filled 

 him with sorrow. Yet he derived consolation from the reflection how much 

 science had been promoted by his departed friends. In the year 1870 he 

 celebrated his Doctors Jubilee, haviug in this year completed the half 

 century of his teaching career. He never sought distinction, though 

 many honours fell to his share. When created a Knight of the Order 

 " Pour la Merite," the honour appeared to him to be almost too great. 

 Imperishable is the remembrance which Gustav Eose has left behind 

 him in Science ; though not imperishable yet more touching is the 

 remembrance which he has left behind him in the hearts of all with whom 



