2. The colored spectral bands being the direct result of the property of interference, or the want of correspondence of the wave lengths due to divergence; the same phenomenon being also observed in convergent light. This is practically illustrated in the hazy definition of the reduced aperture of telescopes, and its peculiarities shown in the spectral rings within and beyond the focus.
3. Chromatic dispersion by our atmosphere, together with selective absorption, also by our atmosphere and its vapors, have been suggested as causes in this curious and complicated phenomena.
In none of the reports descriptive of the phenomena of polarization of the corona is there the slightest allusion to the influence that the diffraction bands may possibly have in modifying or producing the various conditions of polarization observed; although these observations have been made and commented upon during the past twenty-five years.
Investigations now in progress of the modifying relation of the phenomenon of diffraction in its effect upon not only the physical aspect of the corona, but also in some strange spectroscopic anomalies that have been observed near the sun at other times than during a total solar eclipse, will, it is hoped, result in a fuller interpretation of the physical nature of one of the grandest elements of creation—light; let there be more of it.
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