The Rutherfurd Photographic Measures. 133 



Table XYII. — Parallax Equations. 

 Comparison Stars 5 and 53. 













Residuals. 





Plate. 











Scale. 



Arc. 



I 



1. 00a; 



—1.142/ 



+1.90II 



— 1.60 = 



+0.41 



4-o". 1 1 



2 



1. 00 



— 1.13 



+1.90 



— 2.22 = 



— O.21 



— 



.06 



3 



1. 00 



— 1.13 



+1.90 



— 0.91 = 



+1. 10 



+ 



•31 



6 



1. 00 



^.04 



+1-47 



— 1. 71 = 



— 0.41 



— 



.11 



7 



1. 00 



—0.04 



+1.42 



—3-51 = 



—2.28 



— 



.64 



9 



1. 00 



+0.88 



+1.88 



—1.58=0 



4-0.16 



+ 



.04 



10 



1. 00 



+0.89 



+1.85 



—1.85 = 



—0.15 



— 



.04 



11 



1. 00 



+0.90 



+1.83 



—1.32= 



+0.35 



+ 



.10 



12 



1. 00 



+0.90 



+1-83 



— 0.72 = 



4-0.95 



4- 



.27 



13 



1. 00 



+0.90 



+1.S3 



— 1.96 = 



^5.29 



— 



.08 



15 



1. 00 



+1.42 



—1-75 



+3.80 = 



4-0.64 



4- 



.18 



16 



1. 00 



+I-45 



—1-57 



+1.91 = 



— 1.02 



— 



.29 



17 



1. 00 



+145 



—1-57 



+1.65 = 



—1.28 



— • 



.36 



18 



1. 00 



+1-45 



—1-55 



+4.13 = 



4-1.22 



4- 



•34 



19 



1. 00 



+I-45 



—1-55 



+4.29 = 



+ 1.38 



+ 



•39 



20 



1. 00 



+1.45 



—1-55 



-f-2.24 = 



-O.67 



= I4.87 





•19 



Normal Equations. 

 4- i6.oooo.r 4- 9.6600?/ 4- 8.2700II-I- 0.6400=0 

 -(-20.3820 — 12.1142 -(-24.9478 = 

 4-47.2107 — 58.9600 = 



Solution. 

 In units of 2d dec. place of scale. In Arc. 



n = 4- 1.3326 ± 0.1510 n = 4- o".3733 ± 0^.0423 



2/ = — O.1213 ± O.2593 y = — O .0340 ±0 .0726 



x = — 0.6556 ±0.2826 x = — o .1836 ±0 .0792 



Scale. Arc. 



Probable error of one equation = ± 0.72 11 = ± o // .202o 



