THE DESERTS OF AFMCA AND ASIA. 371 



metres) thick, and the thermometer sunk to 22'46 degrees (— 5"3 Centi- 

 grade). Now, this winter manifestation occurred under the latitude of 

 38 degrees (consequently under that of Palermo), and what is equally- 

 very peculiar is, that it did not cause great harm to the vegetation, for 

 the Colonel gathered at this very time 76 plants — a curious example of 

 the elasticity which certain plants possess of accommodating themselves 

 to such extremes of temperature. 



As the distinguished Russian traveller has seen of the Gobi desert 

 more than any of his predecessors, I beg leave to quote his own woi-ds, 

 which give a graphic portrait of the desert ' : ' The general impression 

 produced by the Gobi on the traveller has something gloomy and oppres- 

 sive. During whole weeks the eyes repose on the same objects : unlimited 

 yellow-coloured plains, furrowed rocks or steep hills, on the top of which 

 one perceives sometimes the flying form of the antelope {Antilope gutturosa). 

 The heavily laden camels cross, with measured solemn steps, hundreds 

 and hundreds of miles, and still the desert does not change, keeping always 

 its stern and monotonous appearance. The sun sets, the dark shadows of 

 the night fall, the cloudless sky lights its million of stars, and the caravan 

 stops. Happy to get rid of their loads, the camels lie down around the 

 tents, and their drivers are occupied in preparing a frugal meal. One 

 hour more, and men and animals are soundly asleep, and all around reigns 

 the deathlike silence of the desert, as if no living creature were present. 

 Across the whole of Gobi, from Urga (near the Siberian frontier) to 

 Kalgan (near the frontier of China), there are, except the great post road 

 maintained by the Mongols, several other caravan roads which are usually 

 followed by the caravans carrying tea. Along the post road are stations 

 erected at certain distances, the total number of which amounts to 47 ; 

 and each of these is provided with a well and with a certain number 

 of Mongol tents (Yurt), which represent our post-houses.' 



This long post-road between Urga, Kalgan, and Peking was, during a 

 long time, the only way by which travellers used to cross the Gobi in its 

 whole breadth from north to south. Bat in the numerous publications of 

 those travels, nothing is mentioned except the immense sand- accumulation, 

 without the least hint in reference to the solid rocks on which those sands 

 repose, or to any organic remains. In fact, it seems really that this 

 monotonous road does not offer any interest whatever, for even the sharp- 

 sighted Colonel Prejevalsky was not able to detect there anything of 

 scientific importance ; all he says of the country between Urga and the 

 frontier of China is, that the soil of the Gobi consists of reddish, coarse- 

 grained sand and pebbles belonging to different rocks. Fortunately, 

 when, after concluding his extensive travels, the Colonel returned to 

 Russia, he did not follow the trodden road from Peking to Urga, but took 

 a much more westerly one, so that he crossed the desert in a direction in 

 which it has never been visited previously, viz., from the mountains of 

 Alashan to Urga. He describes this part of the desert as having a very 

 undulated surface, and at certain points intersected by considerable heights 

 composed chiefly of porphyry. In a depression he observed gneiss cropping 

 out through the superficial deposits, and here and there this rock rising 

 like little islands amidst the sea of sand. 



Such denudations of the substratum are of the greatest importance 

 to our knowledge of the solid framework of the desert ; for if we could 



' Col. N. Prejevalsky, Reisen in dcr Mongolei, from the Eussian, by Albin Kohn, 

 2nd edit., p. 15. 



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