“Am I looking grave?” asked Sir Nathaniel inconsequently when he re-entered the room.

“You certainly are, sir.”

“We little thought when first we met that we should be drawn into such a vortex.  Already we are mixed up in robbery, and probably murder, but—a thousand times worse than all the crimes in the calendar—in an affair of ghastly mystery which has no bottom and no end—with forces of the most unnerving kind, which had their origin in an age when the world was different from the world which we know.  We are going back to the origin of superstition—to an age when dragons tore each other in their slime.  We must fear nothing—no conclusion, however improbable, almost impossible it may be.  Life and death is hanging on our judgment, not only for ourselves, but for others whom we love.  Remember, I count on you as I hope you count on me.”

“I do, with all confidence.”

“Then,” said Sir Nathaniel, “let us think justly and boldly and fear nothing, however terrifying it may seem.  I suppose I am to take as exact in every detail your account of all the strange things which happened whilst you were in Diana’s Grove?”

“So far as I know, yes.  Of course I may be mistaken in recollection of some detail or another, but I am certain that in the main what I have said is correct.”

“You feel sure that you saw Lady Arabella seize the negro round the neck, and drag him down with her into the hole?”

“Absolutely certain, sir, otherwise I should have gone to her assistance.”

“We have, then, an account of what happened from an eye-witness whom we trust—that is yourself.  We have also another account, written by Lady Arabella under her own hand.  These two accounts do not agree.  Therefore we must take it that one of the two is lying.”

“Apparently, sir.”

“And that Lady Arabella is the liar!”

“Apparently—as I am not.”

“We must, therefore, try to find a reason for her lying.  She has nothing to fear from Oolanga, who is dead.  Therefore the only reason which could actuate her would be to convince someone else that she was blameless.  This ‘someone’ could not be you, for you had the evidence of your own eyes.  There was no one else present; therefore it must have been an absent person.”

“That seems beyond dispute, sir.”

“There is only one other person whose good opinion she could wish to keep—Edgar Caswall.  He is the only one who fills the bill.  Her lies point to other things besides the death of the African.  She evidently wanted it to be accepted that his falling into the well was his own act.  I cannot suppose that she expected to convince you, the eye-witness; but if she wished later on to spread the story, it was wise of her to try to get your acceptance of it.”

“That is so!”

“Then there were other matters of untruth.  That, for instance, of the ermine collar embroidered with emeralds.  If an understandable reason be required for this, it would be to draw attention away from the green lights which were seen in the room, and especially in the well-hole.  Any unprejudiced person would accept the green lights to be the eyes of a great snake, such as tradition pointed to living in the well-hole.  In fine, therefore, Lady Arabella wanted the general belief to be that there was no snake of the kind in Diana’s Grove.  For my own part, I don’t believe in a partial liar—this art does not deal in veneer; a liar is a liar right through.  Self-interest may prompt falsity of the tongue; but if one prove to be a liar, nothing that he says can ever be believed.  This leads us to the conclusion that because she said or inferred that there was no snake, we should look for one—and expect to find it, too.

“Now let me digress.  I live, and have for many years lived, in Derbyshire, a county more celebrated for its caves than any other county in England.  I have been through them all, and am familiar with every turn of them; as also with other great caves in Kentucky, in France, in Germany, and a host of other places—in many of these are tremendously deep caves of narrow aperture, which are valued by intrepid explorers, who descend narrow gullets of abysmal depth—and sometimes never return.  In many of the caverns in the Peak I am convinced that some of the smaller passages were used in primeval times as the lairs of some of the great serpents of legend and tradition.  It may have been that such caverns were formed in the usual geologic way—bubbles or flaws in the earth’s crust—which were later used by the monsters of the period of the young world.  It may have been, of course, that some of them were worn originally by water; but in time they all found a use when suitable for living monsters.

“This brings us to another point, more difficult to accept and understand than any other requiring belief in a base not usually accepted, or indeed entered on—whether such abnormal growths could have ever changed in their nature.  Some day the study of metabolism may progress so far as to enable us to accept structural changes proceeding from an intellectual or moral base.  We may lean towards a belief that great animal strength may be a sound base for changes of all sorts.  If this be so, what could be a more fitting subject than primeval monsters whose strength was such as to allow a survival of thousands of years?  We do not know yet if brain can increase and develop independently of other parts of the living structure.

“After all, the mediaeval belief in the Philosopher’s Stone which could transmute metals, has its counterpart in the accepted theory of metabolism which changes living tissue.  In an age of investigation like our own, when we are returning to science as the base of wonders—almost of miracles—we should be slow to refuse to accept facts, however impossible they may seem to be.

“Let us suppose a monster of the early days of the world—a dragon of the prime—of vast age running into thousands of years, to whom had been conveyed in some way—it matters not—a brain just sufficient for the beginning of growth.  Suppose the monster to be of incalculable size and of a strength quite abnormal—a veritable incarnation of animal strength.  Suppose this............