226 Permanence of the Butherfurd Photographic Plates. 



Results of the Measures, Plate 18, Y-ooordinate (Rev'd). 



( Continued.) 



Desig. 



of 

 Star. 



Microia. Readings. 



DiflF. 



Mean 

 2 



Screw 



and Div. 



Error. 



Final 

 Reading. 



Otos'r. 



On 

 Star. 



On Scale. 



Line 



15 

 15 

 15 

 15 



47 

 47 

 47 



47 



88 

 88 

 88 

 88 



Reading. 



A28,E 

 W 



42 E 

 W 



A30, E 

 W 



43 E 

 W 



A39,E 

 W 



44 E 

 W 



9-5405 

 9.0180 

 9-4940 

 8-9945 



9-5490 

 9.0480 

 9.5190 

 8.9840 



9.5260 

 9.0240 



9-5055 

 9.0010 



10.0715 

 9.5840 



10.0440 

 9.5660 



9-8385 

 9-3525 

 9-8125 

 9.3000 



I1.1995 

 10.7045 

 1 1. 1845 

 10.6890 



0.5310 

 0.5660 

 0.5500 

 0.5715 



0.2895 

 0.3045 

 0-2935 

 0.3160 



1.6735 

 1.6805 

 1.6790 

 1.6880 



0.2742 

 0.2804 



0.1485 

 0.1524 



0.8385 

 0.8418 



-I-0.0002 

 +0.0002 



+0.0016 

 +0.0016 



— 0.0004 

 — 0.0004 



15.2744 

 15.2806 



47.1501 

 47.1540 



88.8381 

 88.8414 



D. 



J. 



D. 

 J. 



D. 



J. 



