308 THE CHEMISTRY OF THE SUN. [CHA*. 



the old one, and in truth demands phenomena, and simply and 

 sufficiently explains them, which were stumbling-blocks and 

 paradoxes on the old one. 



But we go still more into detail. 



Let us first suppose, to take the simplest case, that the sun 

 when cold will be a solid mass of one pure element, i.e., that 

 the evolution brought about by reduction of temperature shall 

 be along one line only. Let us take iron as the final product. 



FIG. 104. Hypothetical section of solar atmosphere. 



Then the sun's atmosphere on the new theory qud this one 

 element may be represented as follows (see fig. 104) : 



Assume strata A L. Then > 



(1.) The Fraunhofer spectrum will integrate for us the 

 absorption of all strata from A to L. 



(2.J The darkest lines of the Fraunhofer spectrum will be 

 those absorbed nearest the outside of the atmosphere. 



