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ON THE MERIDIAN.- 5 



rampart of the fort, to be secure against the high' winds; but'the'-badnc^ 

 of the weather, occasioned by the setting in of the west monsoon, ren- 

 dered all my endeavours fruitless. I have, however, reason to hope that 

 the observations which have been made at the extremities- of the arc, Y\vill 

 be thought satisfactory. ... 



■ The length of the degree due to the middle point of this section of the 

 arc, or latitude 9 34 43, is found to be 60473, fathoms nearly. Now it 

 may be proper tb notice here, what has already been noticed in giving an 

 account of the former arc, that between Dodagoontah, in latitude 13°, arid 

 the station at Bomasundrum, in latitude 14 , there is a vein of iron ore, 

 which was supposed to have affected the plummet, as some irregularity 

 appeared to exist in the observations 'at those places. The arc] Putchapol- 

 liam and Dodagoontah gave the length of the degree for latitude 11 59 

 54 equal 60529 fathoms, and the arc between Putchapolliam and B-om'a- 

 sundrum gave the degree only 60449 fathoms reduced to the same lati- 

 tude on the elliptick hypothesis. Seeing such a disagreement, it was ne- 

 cessary to recur to the nature of the country, as both those stations are 

 sufficiently remote from mountains to remove any apprehension of a dis- 

 turbance from them. But since no doubt remained as to the existence of 

 some disturbing cause, I attributed it to the effects of this bed of ore, and 

 concluded that the plummet had been drawn to the northward while ob- 

 serving at Dodagoontah, and to the southward while at Bomasundrum, 

 which would give the celestial arc between Putchapolliam and Dodagoon- 

 tah too little, and that between Putchapolliam and Bomasundrum too 

 great, the reverse of which would take place with respect to the length 

 of the degrees in these two arcs. Being confident as to the accura-cy of 

 the observations at both places, and considering the circumstances just 



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