1893-94-] The Interior of the Earth. 



97 



III.— THE INTERIOR OF THE EARTH* 



By Mr T. CUTHBERT DAY, F.C.S. 



(Read Bee. 28, 1893.) 



From the earliest times the nature of the interior of the earth 

 has been an object of mystery and speculation to mankind. 

 The ancients of Greece and Borne placed there the future abode 

 of souls after death, the good inhabiting the Elysian fields, 

 while the bad were relegated to the abysses of Tartarus, the 

 supposed home of desolation and punishment. Even after 

 the death of paganism many Christian believers have referred 

 the locality of hell to the same mysterious and awe-inspiring 

 place, which is generally connected in the human mind with 

 the idea of unquenchable fire. In the Northern mythology 

 the interior was supposed to be inhabited by a singular race 

 of beings, the dwarfs, and we have a picture of their opera- 

 tions underground in the old legend which describes the 

 journey of Skyrnir, the companion or servant of the summer 

 god Frey, to these regions, whither he was sent in order to 

 obtain from the dwarfs the slender but unbreakable chain with 

 which Odin and the rest of the gods intended to bind the 

 savage wolf -giant Fenrir. There he sees these wonderful little 

 people, some leading up veins of precious metal, where they 

 will one day meet the eye of man ; others fashioning rubies, 

 diamonds, and other precious stones ; and still deeper down he 

 finds the swarthy shrivelled race whose business it was to feed 

 with fuel the earth's great central fire. 



To-night we have not to deal with these crude speculations 

 and beliefs ; but I shall endeavour to lay before you, briefly, 



e state of our knowledge, at the present time, with regard to 

 :he material and physical nature of the interior of the globe. 



The earth, as everybody knows, is a globe, having the figure 



of an oblate spheroid. The equatorial diameter measures 



?25-6 miles and the polar diameter 78991 miles, which 



gives a difference in favour of the equatorial diameter of 2 6 "5 



miles. It is supposed by some that this flattening of the 



otheSo^rcef ^ ^ ^^ " Pl '° f ' JUkCS Browue ' s '^J^ Geology,' and 

 VOL. III. 



