168 



EOGEES AND McLEOD ON THE 



It is not necessary to give the residuals, since they are nearly identical with those 

 derived from the values, c = — 0'.06 and a = — 0\34, as given on page 43. 



We have in the observations on this date a clear illustration of the indeterminate 

 character of the algebraical solution of the equations involving a, c, and â^T, especially 

 when there is no reversal of the instrument. As a further illustration, the following 

 solution is given b}' equations (6): — 



The fundamental equations, with weights as on page 5G, and with the assumed 

 values 



c^T.,= 



-0.34 

 -O.OG 



+G.88G 



are as follows : 



The corresponding normal equations are — 



= +0.4215 

 +0.2192 

 —0.1614 

 +0.205.S 

 -0.0081 



+ 10.39GS(t 

 + 0.0008rt 

 - 1.04SSa 

 + 0.0008" 

 + (;.5788(/ 



+0.0008»' 

 +6.69.38»' 

 +0.0008»' 

 -l.G008a' 

 +4.4808»' 



- 1.048SC 

 + 0.0008c 

 +39.0528C 

 + 0.0008c 

 +22.0048C 



+ 0.0008c' 

 - 1.G028C' 

 + O.OOOSc' 

 +23.0288c' 

 -14.2G08c' 



+ 6.5788A7' 

 + 4.4808A?' 

 +22.0048A7' 

 — 14.2G08Ar 

 +28.7008A7' 



Whence ■ 



