![](http://www.alamy.com/thumbs/6/EDB4DFA8-2FBF-4CB6-9A7B-913A89752D14/2AM2JCJ.jpg)
The Astrophysical journal . rew was of \ mm pitch. The dis-tance between two successive orders of a line was taken for variouslines, and all other readings were referred to this interval. It hap-pened that tenths of divisions of the micrometer head correspondednearly to tenth-meters. The average error of setting on agood line was tenth-meters. 1 Haschek (Sitznngsberichte der Kais. der Wiss. in Wien, no, 1901) states thatthe wave-length from a spark depends on the pressure in the spark and also uponthe density of the vapor. But later investigations failed to verify his results. Seen
The Astrophysical journal . rew was of \ mm pitch. The dis-tance between two successive orders of a line was taken for variouslines, and all other readings were referred to this interval. It hap-pened that tenths of divisions of the micrometer head correspondednearly to tenth-meters. The average error of setting on agood line was tenth-meters. 1 Haschek (Sitznngsberichte der Kais. der Wiss. in Wien, no, 1901) states thatthe wave-length from a spark depends on the pressure in the spark and also uponthe density of the vapor. But later investigations failed to verify his results. Seenote in Astrophysical Journal, 14, 201, 1901. 8 G. F. HULL Although a great number of plates were taken, only those weremeasured on which the upper and lower images were nearly equal inintensity and were neither over- nor under-exposed. A photograph inwhich the upper half of the slit had been exposed to the approachingspark and the lower half to the opposite was combined with one forwhich the conditions were reversed. Fig. 2.
Size: 2011px × 1243px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectspectru, bookyear1895