"One evening, going into the laboratory after dark, I observed with astonishment what looked like a lambent flame upon the table. In my alarm I ran forward to put it out, but found that there was no heat in it; lighting my lamp I could no longer see it, but on the table I found a few grains of the stuff I had been experimenting on. Turning out the lamp the light was again visible, and after much thought I concluded that it was similar to the light given by the little creatures called glowworms, and which in its turn somewhat resembles the light that can be seen at times in a pile of decaying fish. I tried many experiments, but as nothing came of them I gave them up, not seeing that any use could come of a fire that gave out no heat. I produced a powder, however, that when rubbed on any substance, became luminous in the dark, presenting an appearance strange and sufficiently alarming to the ignorant. "Thinking the matter over some time ago, I took a little of this powder from the phial in which I had stored it away, and, moistening it, rubbed it on the wall in the form of circles, triangles, and other signs. I did this just before it became dark. As the moisture dried, these figures gradually assumed a luminous appearance. I saw the use to which this could be put in awing a mob, and, setting to work, made a large supply of this powder." "How long does it retain its light, father?" "That is uncertain. For some hours in a darkened room, the light gradually growing fainter, but if a bright day follows, the figures stand out on the following night as brightly as before; while if the day is dull they show up but faintly at night. I see not that any use can come of such a thing, for the light is at all times too faint to be used for reading unless the page is held quite close to it. Come downstairs with me and I will show you the head of one of the old Roman statues that was dug up near Rochester, and which I bought for a few pence last year." They went down into the laboratory. The light was burning. "There you see, Edgar, I have painted this head with the stuff, and now you can see nothing more unusual than if it had been daubed with whitewash. Now I will extinguish the lamp." Prepared as he was, Edgar nevertheless stepped back with an exclamation of surprise and almost awe. The head stood out in the darkness with startling distinctness. It had the effect of being bathed in moonlight, although much more brilliant than even the light of the full moon. It seemed to him, indeed, almost as if a faint wavering light played around it, giving the stern face of the old Roman a sardonic and evil expression. "You can touch it, Edgar, but you will see that there is not the slightest warmth." "It is wonderful, father."