256 Permanence of the Rutherfurd Photographic Plates. 



E.ESULTS OP THE MEASURES, Plate 16, STANDARDS {Continued). 



X-COORDINATE. 



O / 411 II 



Circle right 182 26 22, 26 21. 

 Circle left 26 20, 26 21. 



De.«ig. 

 of 

 Star. 



Microm. Readings. 



Diff. 



Mean 

 2 



Screw 



and Div. 



Error. 



Final 

 Reading. 



Obs'r. 



On 

 Star. 



On Scale. 



Line 



Reading. 



A34,E 

 W 



173 E 

 W 



i8m, E 

 W 



lt4 E 

 W 



9.5220 



9-OI55 

 9.5200 

 9.0275 



9-5305 

 9-0255 

 9-5365 

 9-0235 



28 

 29 

 28 

 29 



100 



lOI 



100 



lOI 



10.7230 

 9. 6640 



10.7190 

 9.6730 



10.4165 

 9-3510 



10.4160 

 9.3480 



1. 2010 

 0.6485 

 1. 1990 

 0.6455 



0.8860 

 0.3255 

 0.8795 

 0.3245 



0.4624 

 0.461 1 



0.3029 

 0.3010 



+.0007 

 +.0007 



+.0007 

 +.0007 



28.9631 

 28.9618 



100.8036 

 100.8017 



D. 

 D. 



D. 

 D. 



Y-COORDINATE. 



O . II I II 



Circle right 92 26 19, 26 19. 

 Circle left 26 21, 26 19. 



Desig. 



of 

 Star. 



Microm. Readings. 



Diff. 



Mean 

 2 



Screw 



and Div. 



Error. 



Final 

 Reading. 



Obs'r. 



On 



Star. 



On Scale. 



Line 



96 

 96 

 96 

 96 



20 

 20 

 20 

 20 



Reading. 



A34,E 

 W 



175 E 

 W 



18 m, E 

 W 



176 E 

 W 



9-5005 

 9.OIIO 

 9-5175 

 8.9945 



9.4800 

 9.0060 



9.5045 

 9.0030 



10.0550 

 9- 5450 



10.0715 

 9.5290 



10.6225 

 10. 1380 

 10.6440 

 10. 1 1 85 



0.5545 

 0.5340 

 0.5540 

 0.5345 



I. 1425 

 I. 1320 



I- 1395 

 I.I155 



0.2721 

 0.2721 



0.5686 

 0.5638 



+0.0012 

 +0.0013 



—0.0005 

 — 0.0006 



96.2733 

 96.2734 



20.5681 

 20.5632 



J. 



J. 



J. 

 J. 



