﻿SxANSriELD & Walmsley. 



Phil. Mag. Ser. 6, Vol. 23, PL IY. 



1. 



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it k X 



8 I s s s s's 2 3s 4 5 



81 



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I 8 min. 



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Green Mercury Line, 5401 A. 



ABERRATION IN DIFFRACTION SPECTRA. 



