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ASTRONOMICAL OBSERVATIONS 



MADE IN THE 

 UPPER PARTS OF HINDOSTA'N, 



AND 



OX A JOURNEY THENCE TO OUJEIN. 



BY WILLIAM HUNTER, ESQ. 



B 



EFORE delivering the following observations, 

 it will be proper to give some account of the 

 instruments with which they are made. The alti- 

 tudes for determining latitudes and time, were taken 

 with a sextant often inches radius, made by Trough- 

 ton : the limb is divided into degrees and thirds of 

 a degree, and the divisions on the vernier go to half 

 minutes ; so that, by the help of the magnifying lens, 

 a difference of ten seconds is sufficiently perceptible. 

 The two specula, being screwed down in their places, 

 do not (as far as I can discover) admit of the princi- 

 pal or vertical adjustment: but the error was almost 

 daily ascertained by the double mensuration of the 

 sun's diameter, and constantly allowed for. It is sub- 

 tractive ; and my determination of its quantity varied 

 from 2' 30" to 3' 30''. These differences may have in 

 part arisen from a real variation in the quantity of this 

 correction ; but I ascribe them chiefly to some inac- 

 curacy in my mensuration of the sun's diameter. 

 Tc form some judgment of the influence this cause 



might 



