378 ALEXANDER VON HUMBOLDT. 



.sive mountain chain composed of several parallel ridges, rising 

 to a height of about 4,600 feet, which, stretching in the same 

 direction as the Andes, due north and south, extend from the 

 tertiary formations near the Sea of Aral to the primary rocks 

 of the Arctic Ocean. June 16 and 17 were occupied in visiting 

 the Imperial laboratories for the cutting of the topaz, the beryl 

 and the amethyst, the gold washings of Schabrowski, the 

 quarries of Rhodonit, and the iron furnaces of Nijnii-Issetsk ; 

 and during the following week, Humboldt and his companions 

 visited Beresow on the lake of Schartasch, Polewskoi, and 

 Grummesch ewskoi. 



An excursion of greater length was then taken northward, 

 through Pischminsk and Neviansk to Nijnii-Tagilsk, the pro- 

 perty of Prince Demidoff, where, on June 27, so late as nine 

 o'clock in the evening, the travellers paid a visit of inspection 

 to the mines. Humboldt found that the platinum fields of this 

 district, as well as those of Sucho-Wissim and Eublowskoi, 

 yielded an amount of ore equal to that procured from Choco in 

 South America. The party then proceeded northward, by way 

 of Kuschwa, Laja, Blagodad, and Nijnii-Turinsk to Bogos- 

 lowsk, for the sake of visiting the extensive gold mines ; whence 

 they made the return journey to lekaterinbo-urg, in the midst 

 of a succession of thunderstorms, through Werchoturje, Alopa- 

 giwsk, Mursinsk, where the topaz and the beryl mines were 

 visited late at night, and lastly Schaitausk. 



The travellers left lekaterinbourg on July 18, and continued 

 their journey, by way of Tioumen, to Tobolsk, on the banks of 

 the Irtysch. There Humboldt .decided to deviate from the 

 route he had laid down ; and, instead of going by way of Omsk 

 and Semipalatna, he went from Tobolsk through Tar a and the 

 steppes of Barabinsk, notorious for their dreaded swarms of 

 stinging insects, to Barnaul, on the river Obi. He proceeded 

 thence to the picturesque Lake of Kalywan, and the rich silver 

 mines of the Snake Mountains, and those of Riddersk and 

 Zyrianowskoi, on the south-western slopes of the Altai Moun- 

 tains. 



After passing the small fortress of Ust-Kamennoigorsk, the 

 travellers arrived on August 19 at Buchtarminsk, on the 

 borders of Chinese Tartary, where Humboldt obtained per- 



