a 



MEASUREMENT OF AN ARC 



terminates at another ftation of obfervation nc^r Daumergidda in the 

 Nizam's dominions, as high as the latitude 18 "^ 3' 23'. 53, being an increafe 

 of 2^ 57' 23'. 32, and making in th©- : whole an = arc of 9° 53 45^24 in 

 amplitude, the longed that haseverbeen meafured on the furfacs of 

 this globe. The great extent of thefe operations, together with the 

 confiftency of the refults, will, independant of any foreign meafure- 

 merits, be eompeteht to eilablilB thib .dlipttc hypothecs with", refpe6t 

 to the figure, of the, earth V Aad thajt this, may be done in the mod 

 fat^isfactory manner, I have cprjtrived to makethe length of this fedion 

 fuch, that it^ middle point may be as near the' latitude of 16° 34 44." 

 as poffibl^, bee a ufe the middle point of the firft fedion falls in 9'J 34' 

 44'; fo that in calculating the fucceffive degrees according to the ellipdc 

 theory, the computed and meafured degrees may be compared. 



In my lafl, it appeared that the mean length of the degree due to 

 th£ iati'.ude of 1 1° 37' 49 , the middle point between Punnm and Nam,' 

 tliabad, was 634^0.3 fathomso Since that paper was fent, there has 

 been a fmali corredioo applied to the bafe near Gooty after comparing 

 the chains with the bEarfs; ft ^ndardfcale, as, will appear in the detailed 

 account of that delicate operation. This corredion has fomewhat 

 increafed the meridional diftance between that h^[e ^nd Terr acondak 

 fouth,. arid confequently the whole terreftrial arc between Namthabad 

 and Pannae is alfo increafed; which now^ives the degree due to latitude 

 11° 37' 4^" equal 60481 .55 fathoms^. However as there are now three 

 feftions, whofe re fpedive middle points lie in 9^ 34' 44"; 13^255'-' 

 and 16" 34'42''; I have thought it bed to take the degrees due to thefe 

 latitudes, as deduced from aQ:ual. obfervations, n^ing edichr. fir fi, with 

 the Fre7ich meafure, then, with the English .mtdL{\xxej and laflly^ with.. 

 the Swedifh meafure; and thence chtdiming ^. general 'iriem vdiiio o€ 

 the polar axis to the equatorial diameter, ~The/r/Z mean 'of thefe .three 



