PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 803 



to produce this condition for the chemical elements of the sun 

 would produce dissociation or isolation of these elements, such as 

 happens with water, which at a high temperature is decomposed 

 and separated into a mixture of chemically indifferent oxygen and 

 hydrogen gases, which combine by cooling, and form water. In 

 like manner, the cooling by radiation from the sun would produce 

 combination at its surface, giving rise to an intensely luminous 

 mist of oxydized compounds, which would radiate light through 

 an atmosphere holding them in suspension, and so intensely hot 

 as to still contain, in an incorabined gaseous form, many of the 

 chemicdl elements. In this way is explained the non-polarized 

 condition of the solar light and its peculiar spectral phenomena. 

 The mist of the oxj-dized particles, tailing toward the center of 

 the sun, again meets a heat of dissociation, so that the process of 

 surface combination is incessantly renewed. The heat of the sun 

 is maintained by the slow shrinking or condensation of its mass ; 

 a diminution of which, equal to one-thousandth of its present 

 diameter, as calculated by Hcmholtz, being sufficient to maintain 

 its present supply of heat for 21,000 years. This is essentially 

 Faye's theory of the sun. 



The Cooling Globe. 



The earth once passed through the same phase which our sun 

 now presents, and finally became a liquid molten mass in which 

 different compounds may have arranged themselves according to 

 their various densities. From what we know of the laws of con- 

 gelation in such bodies as form the earth, we conclude that the 

 solidification of this mass would take place from the center, since 

 rocks, unlike water, are denser in a solid than in a liquid state. 

 Pressure also, according to Hopkins, would favor the solidification 

 of such bodies as compose the globe, and there would, at last, 

 result a solid globe with a scorified surface, probably irregular 

 from various causes, and perhaps not unlike the present surface of 

 our satellite. This crust would contain all the earthy, alkaline, 

 silicious, and metallic elements, while, in the atmosphere above 

 the chlorine, carbon, sulphur, hydrogen, and nitrogen, with any 

 excess of oxj^gen, would constitute an atmosphere of enormous 

 den.sit3\ From this, on cooling, there would be precipitated, at a 

 temperature still very elevated, an acid rain decomposing the 

 silicious surface, setting free its silica in the form of quartz, and 

 forming solutions of chloride of calcium, magnesium and sodium, 



