314 LOSS OF HEAT AND LIGHT IN THE SOLAR SYSTEM. 



teors is greater now than formerly, as to believe that it was greater for- 

 5iierly than now. But Mr. Proctor does not deny, on the contrary he claims, 

 that the nebular hypothesis is true in part. If true in part it may be true 

 ^n all, and this he admits. If we consider our own planet, we find evidence 

 'deeply interwoven in its entire structure which clearly unfolds a past his- 

 tory widely different from its present condition. There is evidence of a 

 former far greater degree of heat than we experience now ; ' heat so intense, 

 indeed, that after passing a probable stage in which all of our metals and 

 solid rocks were held in incandescent vapor, a stage was reached in which 

 (they were still held in a vast, glowing, molten mass so intensely heated as to 

 'drive ofi' in a gaseous vapor all of the waters now collected in our vast 

 'Oceans, and to hold them suspended in a cloud envelope of great thickness. 

 iFrom this condition the earth has gradual!}^ cooled down, by a slow dis. 

 ipersion of its heat, to its present condition. Judging from what has taken 

 iplace in t'le past, we have reason to believe that this dispersion of heat will 

 •continue until the entire heat force of the earth is exhausted ; until the 

 'earth becomes a cold, dead body, destitute of life, as we now find its at- 

 rtendant satellite. The moon is believed to be now destitute of heat, desti- 

 tute of life, and destitute of an atmosphere and of water upon its surface ; 

 its face pitted over with deep valleys, environed by high moantains ; the 

 •mountain shadows so vast as to be seen with the naked eye. This manifest 

 ■display of former volcanic action gives unmistakeable evidence of immense 

 'j>ast forces caused by internal heat; forces which long since have ceased. 

 The atmosphere and water, which no doubt prevailed on the moon's surface 

 daring its active stage, have disappeared, probably swallowed u]3 in some 

 ..other form in its interior. 



M we consider the inner planets, those nearer the sun than the earth, 

 ■•'■and. -conforming nearest to it in size, we find their present condition very 

 ! similar to that of the earth. It we look to the larger outer planets, 

 - especlaflly to Jupiter and Saturn, we find them still in a state of glowing 

 ' heat, with the water, which will be ultimately collected together upon their 

 ; surfaces in vast oceans, now held in vapor, enveloping them in vast cloud 

 masses. The great ruler of the day, the mighty sun, whose mass is so supe- 

 irrior to all of its attendant planets, and to which it has given birth, is still 

 vfar more intensely heated than any of them. His heat is so intense, in- 

 ■ deed, as to drive off his lighter metals, such as iron, nickel, sodium, &c., in 

 ^vapor, as our water is suspended in vapor in the earth's atmosphere. Such 

 is beli<eved to fej the present condition of our solar system by those most 

 .distinguished in physics. 



llf the sun and planets have a common origin, the degree of heat in- 

 ttensity iaa.ust have been at one time homogeneous, and the difterence now 

 iprevs/ili^g the result of separation and consequent difference in mass, which 

 idesti«©yed the former homogeneity by changed condition or relation. It is 

 \well 'known that a small body, heated to the same degree, loses its heat 

 QJEUiiSa sooner than a larger one. 



