"Yes, it is a strange thing; but is, so far as I can see, of no use save as a wonder, and it is just one of those wonders that to most people would seem to be magical. I showed it a short time ago to the prior, having explained to him beforehand how I had discovered it. He is above the superstitions of folks in general, and knowing that I could have no motive in deceiving him, was much interested; but he said to me, 'This is one of the things that were best concealed. I can quite understand that there are many things in nature of which we are ignorant. I know that what you say of decayed fish sometimes giving out light like this is perfectly true, and everyone knows that the glowworms, when the weather is damp, light up the banks and fields, although no heat can be felt. Doubtless in your researches on bones you have discovered some substance akin to that which causes the light in those cases, but you would never persuade the vulgar of this. "'Nay, there are even churchmen and prelates who would view it as magic. Therefore, my friend, seeing that, as you say, the powder is not likely to be of any use to man, I should say that it were best that you destroy it, for if whispers of it got abroad you might well be accused of dealing in magic. All knowledge of things beyond them is magic to the ignorant. Roger Bacon was treated as a magician, and I doubt not that this will ever be the case with all those who are more learned than their fellow-men. Therefore my advice to you is, burn the stuff and say naught about it.' "I did not take his advice, Edgar, for it seemed to me that it might well be used to awe any unruly mob that might come hither at night to attack me. I have made an experiment that, though I believe not in the supernatural, would have frightened me had I seen it without knowing anything of its nature. You know that old skull that was dug up out of the garden last month, I have hung the lower jaw on wires so that it can be moved, and have to-day painted it, and now I will blow out the light again, and then take it from the cupboard." A moment later the room was in darkness, and then an exclamation of surprise and almost terror rose from Edgar. In front of him there was a gibbering skull, the lower jaw wagging up and down, as if engaging in noiseless laughter, It was much more brilliant than the stone head had been, and a lambent flame played round it. "What think ye of that, Edgar?" "It is ghastly, sir, horrible!" "It is not a pleasant object," his father said, quietly, as he struck the tinder and again lighted the lamp. "I fancy, Edgar, that if a mob of people were to break down the door and find themselves confronted by that object they would fly in terror." "Assuredly they would, father; they would not stop running this side of Dartford. Even though I expected it, the sight sent a shiver through me, and my teeth well-nigh chattered. But this would only avail in case of a night attack."