OBSETCVATIONS WITH THE ZENITH TELESCOPE. 



329 



Group 



No. 



B.A.C. 



al892 



al89S 



mn 



S1S03 



n' 



Cor. for 

 Curvature 





1 



5941 

 6000 



h m s 

 17 29 55.26 

 17 37 35.10 



58.05 

 34.74 



1 II 



12 38 20.18 

 68 48 28.08 



II 



17.31 

 20.44 



— .2250 

 + .3151 



II 



+ .10 





2 



0122 

 6143 



17 57 3.41 



18 2 13.74 



2.37 

 10.58 



72 54.91 

 9 33 55.88 



54,64 

 56.18 



— .0078 

 + .0969 



+ .11 





3 



6193 

 6203 



18 9 28.01 

 18 12 17.07 



30.61 

 18.92 



38 44 36.44 

 42 7 21.02 



37.28 

 22.70 



+ .0043 

 + .0024 



+ .06 



XI 



4 



6232 

 0258 



18 15 42.19 

 18 18 57.06 



44.51 

 58.47 



29 37 10.65 

 51 14 55.90 



12.03 

 57.54 



-|- .0102 

 — .0122 



-1- .00 





5 



6300 

 6348 



18 25 7.00 

 18 30 42.63 



9.55 

 43.66 



23 47 40.74 

 56 57 40.84 



42.95 

 49.51 



+ .0137 

 — .0137 



+ .07 





6 



6373 

 6387 



18 37 5.70 

 18 41 0.90 



6.42 

 3.48 



00 36 38.58 

 20 26 35.08 



41.80 

 38.91 



+ .0451 

 — .3341 



+ .07 





7 



6476 

 6491 



18 51 50.27 

 18 54 54.24 



57.85 

 56.48 



48 43 27.97 

 82 32 29.85 



32.35 

 34.61 



— .1210 

 + -0029 



+ .06 





8 



6534 



0579 



19 50.89 

 19 9 17.51 



53.17 

 19.08 



31 34 59.88 

 49 39 8.10 



65.07 

 14.09 



— .0706 

 -1- .6214 



+ .00 



The Latitude Observations. 



The details of the latitude determination are given in the pages following. The 

 expression for the latitude is as follows : 



f = J (6 | £>) + £72 (M — M') | id l(n — «,') — («' — «)] + (to |- m') + | (r — r>) 



M and M are the micrometer readings. 



n, s, n' , s' , the readings of the north and south ends of the levels for the two 



stars. 

 m and ml, the correction for curvature. 

 r and r', the corrections for refraction. 

 The columns which seem to call for explanation are as follows : 

 Column P gives the position of the instrument. 



D, Direct. The telescope east when pointed south of the zenith. 

 R, Kevcrse. The telescope west when pointed south of the zenith. 

 C, The correction on account of progressive errors of the screw. 

 Levels A and B, the value of (n-n') — (V--,s) for each level. 

 Columnn 8 gives the sum of the corrections for Aii? given on page 322 with that 

 for curvature found in the last column of the star list. 



In case of those pairs observed with threads II and IV the correction given on page 

 323 is included. 



Column A gives the reduction on account of the adopted value of the Constant of 

 Aberration, to be explained later. 



