OF THE RIVER SETLEJ. 405 



APPENDIX. 



THE journey of which I have attempted to give some account in the 

 preceding pages was undertaken as before mentioned, for the purpose of 

 laying down the course and levels of the River Setlej. It will be pro- 

 per therefore now to give an idea of the manner in which these two ob- 

 jects were accomplished and also to indicate some of the results. This ac- 

 count of the operations has been separated from the .Narrative as little likely 

 to afford interest to the general reader. A reference to the accompanying 

 Map will render what follows more intelligible. 



1. The particulars on which are founded the positions of the principal 

 points in the mountain survey between the Setlej and Alakananda rivers 

 have been detailed with sufficient minuteness in the preceding volume of 

 the Researches. Of those points however depending on the chain of 

 Triangles, but few offer themselves to the assistance of the Surveyor in his 

 task of laying down the course of this river. A great part of the route 

 described in the preceding pages lies north of the snowy Peaks ; and it 

 had not appeared possible at that time to carry any connecting triangles 

 across that range. The points of verification therefore on which the ac- 

 companying Map depends, and the elevations indicated in the Section 

 being obtained (with only one exception) by less accurate methods than 

 those on which the southern portion of the Map rests, it is my intention 

 to give a brief but particular account of the data on which they are 

 founded. 



2. The first of these (and the most to be depended on I consider) is the 

 latitude of the place. The following Table contains the results of all the ob- 

 servations 1 made. The instrument was Troughton's Circle, No. 44, men- 

 tioned in the former paper. Although it was free as far as I could ever 

 perceive from all collimation, yet, to render the results entirely indepcn- 



