274 THE GOBI AM) SAHARA DESERTS. 



down with terrific force, and for an hour or two 

 afterwards large rivers continued to flow, silting up 

 the wells (always dug on the lower ground) with 

 mud and sand. It would be impossible to travel 

 here without a guide thoroughly acquainted with 

 the country ; for destruction lies in wait for you at 

 every step. In fact this desert, like that of Ala-shan, 

 is so terrible that, in comparison with it, the deserts 

 of Northern Tibet may be called fruitful. There, at 

 all events, you may often find water and good pas- 

 ture-land in the valleys ; here, there is neither the one 

 nor the other, not even a single oasis ; everyw^here 

 the silence of the valley of death. 



The well-known Sahara ^ can hardly be more 

 terrible than these deserts, which extend for many 

 hundreds of miles in length and breadth. The 

 Hurku hills, where we crossed, are the northern defi- 

 nition of the wildest and most sterile part of the Gobi, 

 and form a distinct chain with a direction from SE. 

 to WNW. ; how far either way we could not say 

 positively ; but, according to the information we re- 

 ceived from the natives, they are prolonged for a great 

 distance towards the south-east, reaching the moun- 

 tains bordering the valley of the Hoang-ho, while on 



' In the Sahara desert we find the same diversity in composition 

 and altitude ; the same immense tracts of shingly and sahne soil ; the 

 same loose drifting sands, with occasional patches of rocky ground 

 covered with thorny scrub, while at distant intervals an oasis or islet 

 of vegetation occurs. Such are also the characteristics of the great 

 deserts of Persia and Arabia, which form the prolongation eastward 

 and northward of the Sahara • — ' the whole tract from the Sahara to the 

 (Gobi or) Shamo pointing at once to similarity of conditions and same- 

 ness of geological origin.' (See Page's Physical Geography, p. 104.) — M. 



