before the Geographical Society, May 27, 1867. 33 
grand generalizations, when he was led to believe that the 
Thian-Shan—the great axial range of Central Asia—must be 
essentially one of volcanic eruption. 
Influenced, doubtless, by his — papas of the 
Andes of South America, and the rise to their summits of ac- 
tive volcanoes, the great traveller was zen na disally disposed to 
apply the same inference to the lofty chains of Central Asia; 
the more so as all the imperfect data he could collect seemed 
~ indicate the existence of rocks of that class 
ut as soon as the PhiansShas was examined by the only 
often alteri C4 ioaien: into crystallized Ter and elevating them 
to enormous altitudes, without exhibiting any true igneous 
rocks. 
Having already twice a to the recent discoveries in 
Asia by the Russians, and we having endeavored to do honor 
to them by the award of our Founder’s Medal to one of the 
most distinguished Russian explorers, it is now my pleasing 
duty to advert to others of their recent labors in that quarter 
of the globe, 
On former occasions I have dwelt upon the explorations of 
Eastern Siberia and the affluents of the grand River Amur and 
the mountains to the north. Let us now turn to Central Asia 
proper, and see what good documents have been furnished by 
the different men of science who have explored those oe 
I gather from the ealleine Lh ee tee Geographical So- 
ciety that the communica MM. Semenof, Mover aie 
Poltarazky, Abramof, Bakkof  Goloubel and Printz tz, explain 
the physical conformation of tracts and. ‘a eames riches of 
regions never before reached in modern tim 
Of most of these hitherto promi wil ee the Rus- 
Journeys from Siberia to Pekin, i ittins neler, the physi- 
cian to. the Russian mission in China, has d down upon a 
map all the different known roads acros shoei of w 
sian explorers have prepared or are To faciliate ~ ee 
that which is called the post road is 1760 versts long, between 
Kiachta and Pekin, with 68 relays. If the telegraph, which 
Am. Jour. Sc1.—Sreconp Szrres, Vou. XLV, No. 133.—Jan., 1568. 
3° 
