"The nethermost caverns," wrote the mad Arab, "are not for the fathoming of eyes that see; for their marvels are strange and terrific. Cursed the ground where dead thoughts live new and oddly bodied, and evil the mind that is held by no head, Wisely did Ibn Schacabac say that happy is the tomb where no wizard hath lain, and happy the town at night whose wizards are all in ashes. For it is of old rumor that the soul of the devil-bought hastes not from his charnel clay, but fats and instructs the very worm that gnaws; till out of corruption horrid life springs, and the dull scavengers of earth wax crafty to vex it and swell monstrous to plague it. Great holes secretly are digged where earth's pores ought to suffice, and things have learnt to walk that ought to crawl."