C. Janssen, a spectroscopic method for observing the solar prominences in daylight, and the names of both astronomers appear on a medal which was struck by the French government in 1872 to commemorate the discovery.
At the great Indian eclipse of 1868 he demonstrated the gaseous nature of the red prominences, and devised a method of observing them under ordinary daylight conditions.
Characterized by possessing only a few teeth, on the posterior part of the maxillaries, on the palatines and Coronelline Nymphophidium, the same effect is reached by two prominences at the base of the skull.
In solar physics Huggins suggested a spectroscopic method for viewing the red prominences in daylight; and his experiments went far towards settling a much-disputed question regarding the solar distribution of calcium.
In the general solar spectrum this element is represented by a large number of lines, but in the spectrum of the prominences and chromosphere one pair only can be detected.
