THE numerous absorption spectra of soluble substances which have been described hitherto, have referred as a rule to the solutions of the substances, and but rarely to the solid substances themselves.

This causes an absorption spectra, as shown below. Because the energy levels are the same, the lines in the emission spectra of an element are in the same position as the lines in the absorption ...

WE have recently been investigating the far ultra-violet absorption spectra of a number of organic compounds of the type R 1 COOR 2; R being an alkyl group or a hydrogen atom. It has been found ...