1855.] Notes on Eastern Thibet. 227 



drains ? and Is there more arable land in Thibet, than admits of being 

 irrigated from the rivers ? 



To answer the first question, it would be best to refer to the sta- 

 tistics of the Nile irrigation, in illustration of the extent to which 

 land on either side of a river may be irrigated by artificial means, not 

 by the overflowing of its banks which is not usual by the Taroo of 

 Thibet, and is therefore not be taken into the comparison. I have 

 not the means of making this comparison. But to reply to the 

 second question I have taken much pains to collect facts, the most 

 prominent of which are as follow : — ■ 



1st. The culturable land on either bank of the Painom river, 

 from its source to Digarchi, has not a maximum breadth anywhere of 

 more than four miles, i. e. eight miles in all for the extreme breadth. 

 In many places however, the river is closely confined by mountains. 



2nd. From Digarchi to Griangtchi on the Yaroo one day's sail, 

 the culturable land on either side the Yaroo varies from two to 

 four miles. 



3rd. From Giangtchi till the Yaroo escapes from the Kambola 

 range, its course is exceedingly tortuous, generally through great 

 mountains, and it has but a very narrow bed of culturable land in a 

 few places. It is closely pressed in by great mountain ranges in 

 the Kambola district, and elsewhere in this portion. 



4th. I allow the utmost extent of culturable land ever given to 

 me by an informant for the Yaroo valley from the point at which it 

 leaves the Kambola range entirely to the junction of the Kechoo or 

 Lassa river ; and that is a total breadth both banks included varying 

 from 20 to 40 miles. There is more flat land on the South than on 

 North bank of the Yaroo. 



5th. The Kechoo River is closely hemmed in by mountains on 

 the Eastern bank ; on the Western bank it has a belt of about 4 

 miles of culturable land only. 



These particulars will afford some assistance for reckoning the 

 culturable area of the finest part of Eastern Thibet, and will shew it 

 to be very small indeed, compared with the total area of this rugged 

 country, and it is universally asserted that the land is everywhere 

 dependent on river irrigation for its fertility. On this subject M. 

 Hue says " Poulon, fine purple cloth, scented sticks and wooden 



