Permanence of the Butherfurd Photographic Plates. 245 



Results of the Measures, Plate 24, Standards. 

 Date of Measures, 1895, ^^c, 18. Y-coordinate (Rev'd). 



O / II I II 



Temperature, 66.2, 64.9. Circle right 272 20 30, 20 32. 



Runs, +.0210, +.0210. Circle left 20 30, 20 32. 



Desig. 



of 

 Star. 



Microm. Readings. 



Difif. 



Mean 

 2 



Screw 

 and DiT. 

 Error. 



Final 

 Reading. 



Obs'r. 



On 



Star. 



On Scale. 



Line 



Reading. 



A34,E 

 W 



125 E 

 W 



i8m, E 

 W 



126 E 

 W 



90395 

 9-5235 

 9.0360 

 9-5350 



9-0185 

 9-5280 

 9.0405 

 9-5035 



36 

 36 

 36 

 36 



112 

 112 

 112 

 112 



9-8085 

 10.3690 



9.8000 

 10.3800 



9-3705 

 9.9625 



9-3945 

 99405 



0. 7600 



0.8455 

 0. 7640 

 0.8450 



0.3520 

 0.4345 

 0.3540 

 0.4370 



0.4036 

 0.4022 



0. 1966 

 0.1978 



+.0018 

 + .0018 



— .0006 

 — .CO06 



36.4054 

 36.4040 



112. i960 



112. 1972 



D. 

 D. 



D. 

 D. 



X-cooRDiNATE (Rev'd). 



O / 111,1 



Circle right 2 20 30, 20 32. 

 Circle left 20 31, 20 33. 



Desig. 



of 



Star. 



Microm. Readings. 



Diflf. 



Mean 

 2 



Screw 

 and Div. 

 Error. 



Final 

 Reading. 



Obs'r. 



On 

 Star. 



On Scale. 



Line 



Reading. 



A34,E 

 W 



127 E 

 W 



18 m, E 

 W 



128 E 

 W 



8.9745 

 9-4805 

 9.0310 

 9.5000 



8.9790 

 9.4940 



8.9995 

 9.4695 



103 



lOI 



103 



lOI 



31 

 30 

 31 

 30 



9.3690 

 10.9825 



9-4310 

 10.9985 



9-8995 

 9-5565 

 9.9205 

 9-5340 



0.3945 

 1.5020 

 0.4000 

 1.4985 



0.9205 

 0.0625 

 0.9210 

 0.0645 



0.4741 

 0.4746 



0.2458 

 0. 2464 



— .0004 

 — .0004 



+ .0023 

 +.0023 



102.4737 

 102.4742 



30.7481 

 30.7487 



J. 

 J. 



J. 

 J. 



Annals N. Y. Acad. Sci., IX, November, 1896. — 17 



