OF ARTS AND SCIENCES. 159 



9. 



For Greenwich e= +.028 



Washington, I = +.008 



Oxford = +.029 



Paris = +.036 



Melbourne = +.054 



Edinburgh = +.036 



Brussels = +.056 



Washington, II = +.057 



Harvard College = +.019 



Subtracting the values of e, we have Table V. 



Table VI. is formed by subtracting from the residuals in Table V. the pro- 

 visional corrections depending on the Declination, already obtained. From the 

 residuals of Table VI. are found the following periodic equations of single 



period : — 



s. p. 



For Greenwich r = — .007 sin a +.011 cos a. 



Washington, I r = —.009 sin a +.007 cos a. 



Oxford »■ = — .014 sin a +.021 cos a. 



Paris r = — .024 sin a +.021 cos a. 



Melbourne r = — .034 sin a +.021 cos a. 



Edinburgh r = — .013 sin a +.01G cos a. 



Brussels r = — .039 sin a +.022 cos a. 



Washington, II r = —.042 sin a +.019 cos a. 



Harvard College . . . . r = — .003 sin a +.002 cos a. 



Computing the values of r for each star, and subtracting from the residuals in 

 Table VI., we have Table VII. 



From the residuals of Table VII., we have the following normal equations 

 for the more accurate determination of a and b: — 



Green- Wash. Mel- Brus- "Wash, 



wich. I. Oxford. Paris, bourne, sels. II. 



3.79Aa+ 4.38A6=Sr/'sind = — 19 +6—9 —13 +0 +20 —17 



4.38Aa+28.29A6==Sr//cos^ = — 76 +34 +1 —2 +21 +34 +81 



Edinburgh. Harvard CoUege. 



2.68 Aa + 5.45 A6 =2 r" sin (5 = 8.66 Aa + 4.86 A6 =2 r" sin (J = + 34 

 5.45 Aa +23.48 A6 =2 r" cos S = —88 4.86 Aa +26.43 A6 =2 r" cos 6 = +115 



Whence : 



,«. s. 



For Greenwich Aa = —.003 A6 = —.002 



Washington, I = +.001 = +.001 



Oxford = —002 = +.000 



Paris = —005 = +.001 



Melbourne = —.001 = +.001 



Edmburgh = +.014 = —.007 



Brussels = +.004 = +.001 



Washington, II = —.009 = +.004 



Harvard College .... = +.004 = +.004 



Subtracting the values of r, computed with these coefficients, from the residuals 

 of Table VII., we have Table VIII. 



