320 



Rutherfurd Photographic Measures. 



Table Y. — Parallax Equations. 

 Comparison Stars i and j. 



o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 

 o 



Normal Equations. 



4-21.0000.-c +15.3700?/ — 5.8200" — 3.9200 = 



-1-37.8627 —0.3251 — 1.5679 = 



+8.3404 —13.2118 = 



V 



— 0.23 



+3-09 

 + 1.02 



—3-79 

 +0.13 



— O. II 



—068 



—0.73 

 — 0.21 



—0.35 

 —0.51 

 +0.15 

 — 2.06 



-3.83 

 + 1.60 

 —0.59 

 +1.00 



+1-30 

 +1.44 



+ 1.25 

 +2.08 



= 58.95 



o 

 o 

 o 



Solution. 



In units 2d dec. place. 



■K = +2.3578 ±0.4923 IT : 



y = —0.3975 ±0.2366 y -. 

 X =r= +1.1310 ±0.2664 •'*'■ - 



Probable error of one equation = 



In Arc. 



