OPERATIONS IN THE PENINSULA. 



S65 



The Arc comprehended hy the 3Ieridkins of Savendroog 

 and Yerracondah. 



Let S and Y be the stations at Savendroo^^ and Yer- 

 racotulah respectively, 

 and let the latitude of 

 Y be deduced from 

 tliat of S, the angles 

 PSY and PYS having 

 been observed. Let 

 SR be a great circle 

 perpendicular to the 

 meridian SP at S, and 

 St' a parallel of lati- 

 tude at the same point 

 S. Here the angle 

 RSY = PSY - 90 r: 

 2° 47' 5 '.34, and the angle RYS being the observed 

 angle at Y = 86° 59' 4r'.33. These angles being 

 corrected for the chords, the supplement to their sum 

 will be the chord angle at R in the spheriodical tri- 

 angle SRY. Let the chords of SR and YR be com^ 

 puted with the corrected angles, then if the angle at 

 R be augmented by the ditlerence between the sum 

 of the corrections for the other two ansrles and the 

 spherical excess, it will become 90' 13 14'.74, or such 

 as would have been observed at R. Hence ISO** — 

 A SRY = 89''46'45".26 the angle tllS, and by con- 

 sidering the triangle St'R as a plane one, the small 



angle tSR is equal -^^-^- = 0° 6' V".S7- With 



this angle, and the angle tRS, and the distance SR, 

 as found above, the small side tR is had = 675.8(5 

 feet, which added to RY = 17067.72, gives t Y = 

 17743.58 feet, the distance between the parallels of 

 S and Y. But 17743.58 feet is equal to an arc on 

 the meridian of 2' 55-98, and this deducted from the 

 latitude oi Sa-vendroog, gives 12' 52' 14^26 for the la- 

 titude o'i Yerracondali. 



Hence, with the co-latitudes of Savcndroog and 



