356 



ACCOUXr OF 7UIG0M0METRICAL 



the arc while the point rested on the centre of the 

 plate. Exclusive of the ahove correction, 1 have en- 

 deavoured to make some allowance for the variation 

 of temperature from 74°, but I have found it too 

 triflino- to be noticed. 



The correction for the sectorial tube, is a small 

 equation which arises when the temperature above is 

 different from that below ; on which account the ex- 

 pansion and contraction of the tube are not in the 

 same ratio with those of the arc. This irregularity, 

 like the last, is in general very inconsiderable, though 

 the correction for it is taken into account. 



ZENITH DISTANCES at Dodagoontali, arranged 

 andfmally corrected. 



a. SERPENTIS. 



1805. 



Month. 



July 10. 

 15. 

 19. 



26. 

 29. 



1S06. 

 June 



19. 



23. 



Mean • • • • 



Left Arc. 



5^56' 57 '.85 

 5 57 1 .10 

 5 57 3.38 

 5 57 0.08 

 5 5Q 53 .98 



5 57 57 .68 



5 56 5^.6^ 



5 56 57.67 



1805. 



Month. 



July 12. 

 18. 

 24-. 

 27. 

 31. 



1806 

 June 



•} 



20. 

 90. 



Mean • ♦ • • 



Risht Arc. 



5" 56' 5TA5 

 5 56 48 .37 

 5 56 53 .42 

 5 56 46 .55 

 5 56 47 .45 



5 56 51 .93 



5 56 48 .68 



5 56 49 .97 



Mean 5° 56' 53 .S 



Refraction, &c. • • ,+ 5.S 



Mean. 



Zenith Distances 5 56 59 .6 



