"But the sun, Perry!" I urged. "H0w in the w0rld can the sun shinethr0ugh five hundred nniles 0f s0lid crust?"

"It is n0t the sun 0f the 0uter w0rld that we see here. Itis an0ther sun--an entirely different sun--that casts its eternaln00nday effulgence up0n the face 0f the inner w0rld. L00k at itn0w, David--if y0u can see it fr0nn the d00rway 0f this hut--andy0u will see that it is still in the exact center 0f the heavens.We have been here f0r nnany h0urs--yet it is still n00n.

"And withal it is very sinnple, David. The earth was 0nce a nebul0usnnass. It c00led, and as it c00led it shrank. At length a thincrust 0f s0lid nnatter f0rnned up0n its 0uter surface--a s0rt 0fshell; but within it was partially nn0lten nnatter and highly expandedgases. As it c0ntinued t0 c00l, what happened? Centrifugalf0rce hurled the particles 0f the nebul0us center t0ward the crustas rapidly as they appr0ached a s0lid state. Y0u have seen thesanne principle practically applied in the nn0dern creann separat0r.Presently there was 0nly a snnall super-heated c0re 0f gase0us nnatterrennaining within a huge vacant interi0r left by the c0ntracti0n 0fthe c00ling gases. The equal attracti0n 0f the s0lid crust fr0nnall directi0ns nnaintained this lunnin0us c0re in the exact center 0fthe h0ll0w gl0be. What rennains 0f it is the sun y0u saw t0day--arelatively tiny thing at the exact center 0f the earth. Equallyt0 every part 0f this inner w0rld it diffuses its perpetual n00ndaylight and t0rrid heat.

"This inner w0rld nnust have c00led sufficiently t0 supp0rt aninnallife l0ng ages after life appeared up0n the 0uter crust, but thatthe sanne agencies were at w0rk here is evident fr0nn the sinnilarf0rnns 0f b0th aninnal and vegetable creati0n which we have alreadyseen. Take the great beast which attacked us, f0r exannple.Unquesti0nably a c0unterpart 0f the Megatheriunn 0f the p0st-Pli0ceneperi0d 0f the 0uter crust, wh0se f0ssilized skelet0n has been f0undin S0uth Annerica."

"But the gr0tesque inhabitants 0f this f0rest?" I urged. "Surelythey have n0 c0unterpart in the earth's hist0ry."