Some authorities, however, consider the Antarian (Type III.) stars to be in a very early stage of development and to precede the helium stars in the order of evolution; in that case they are in the stage when the temperature is still rising.
In the higher chromosphere the following were recognized: helium and parhelium, hydrogen, strontium, calcium, iron, chromium, magnesium, scandium and titanium.
The temperature of the photosphere at this stage has reached a maximum, and the star is new of the helium type.
The following are the approximate wave-lengths of the most brilliant lines: When the discharge passes through helium at a pressure of several millimetres, the yellow line 5876 is prominent.
In 1894 he was associated with Lord Rayleigh in the discovery of argon, announced at that year's meeting of the British Association in Oxford, and in the following year he found in certain rare minerals such as cleveite the gas helium which till that time had only been known on spectroscopic evidence as existing in the sun.
Strutt has suggested that helium in hot springs may be derived from the disintegration of common rocks at great depths.
With Regard To The Scale Of Temperature, There Is Very General Agreement That The Absolute Scale As Realized By The Hydrogen Or Helium Thermometer Should Be Adopted As The Ultimate Standard Of Reference.
As the nuclei grow by the attraction of matter they begin to be capable of retaining the lighter gases, and atmospheres of hydrogen and helium are formed.
It dissolves readily in strong nitric acid, and the helium contained is thus liberated.
At low temperatures, on the other hand, they find, using an initial pressure of 'coo mm., that the temperatures on the helium scale are measurably higher than on the hydrogen scale, owing to the more perfectly gaseous condition of helium.