“You make the glass invisible by putting it into a liquid of nearly the same refractive index; a transparent thing becomes invisible if it is put in any medium of almost the same refractive index. And if you will consider only a second, you will see also that the powder of glass might be made to vanish in air, if its refractive index could be made the same as that of air; for then there would be no refraction or reflection as the light passed from glass to air.”

“Yes, yes,” said Kemp. “But a man’s not powdered glass!”

“No,” said Griffin. “He’s more transparent!”

“Nonsense!”

“That from a doctor! How one forgets! Have you already forgotten your physics, in ten years? Just think of all the things that are transparent and seem not to be so. Paper, for instance, is made up of transparent fibres, and it is white and opaque only for the same reason that a powder of glass is white and opaque. Oil white paper, fill up the interstices between the particles with oil so that there is no longer refraction or reflection except at the surfaces, and it becomes as transparent as glass. And not only paper, but cotton fibre, linen fibre, wool fibre, woody fibre, and bone, Kemp, flesh, Kemp, hair, Kemp, nails and nerves, Kemp, in in fact the whole fabric of a man except the red of his blood and the black pigment of hair, are all made up of transparent, colourless tissue. So little suffices to make us visible one to the other. For the most part the fibres of a living creature are no more opaque than water.”

“Great Heavens!” cried Kemp. “Of course, of course! I was thinking only last night of the sea larvae and all jelly-fish!”

“Now you have me! And all that I knew and had in mind a year after I left London — six years ago. But I kept it to myself. I had to do my work under frightful disadvantages. Oliver, my professor, was a scientific bounder, a journalist by instinct, a thief of ideas — he was always prying! And you know the knavish system of the scientific world. I simply would not publish, and let him share my credit. I went on working; I got nearer and nearer making my formula into an experiment, a reality. I told no living soul, because I meant to flash my work upon the world with crushing effect and become famous at a blow. I took up the question of pigments to fill up certain gaps. And suddenly, not by design but by accident, I made a discovery in physiology.”

“Yes?”

“You know the red colouring matter of blood; it can be made white — colourless — and remain with all the functions it has now!”

Kemp gave a cry of incredulous amazement.

The Invisible Man rose and began pacing the little study. “You may well exclaim. I remember that night. It was late at night — in the daytime one was bothered with the gaping, silly students — and I worked then sometimes till dawn. It came suddenly, splendid and complete in my mind. I was alone; the laboratory was still, with the tall lights burning brightly and silently. In all my great moments I have been alone. ‘One could make an animal — a tissue — transparent! One could make it invisible! All except the pigments — I could be invisible!’ I said, suddenly realising what it meant to be an albino with such knowledge. It was overwhelming. I left the filtering I was doing, and went and stared out of the great window at the stars. ‘I could be invisible!’ I repeated.

Indeed, as we found when we also reached the spot, it was something very different. At the foot of a pretty big pine and involved in a green creeper, which had even partly lifted some of the smaller bones, a human skeleton lay, with a few shreds of clothing, on the ground. I believe a chill struck for a moment to every heart.

“He was a seaman,” said George Merry, who, bolder than the rest, had gone up close and was examining the rags of clothing. “Leastways, this is good sea–cloth.”

“Aye, aye,” said Silver; “like enough; you wouldn’t look to find a bishop here, I reckon. But what sort of a way is that for bones to lie? ’Tain’t in natur’.”

Indeed, on a second glance, it seemed impossible to fancy that the body was in a natural position. But for some disarray (the work, perhaps, of the birds that had fed upon him or of the slow–growing creeper that had gradually enveloped his remains) the man lay perfectly straight—his feet pointing in one direction, his hands, raised above his head like a diver’s, pointing directly in the opposite.

“I’ve taken a notion into my old numbskull,” observed Silver. “Here’s the compass; there’s the tip–top p’int o’ Skeleton Island, stickin’ out like a tooth. Just take a bearing, will you, along the line of them bones.”

It was done. The body pointed straight in the direction of the island, and the compass read duly E.S.E. and by E.

“I thought so,” cried the cook; “this here is a p’inter. Right up there is our line for the Pole Star and the jolly dollars. But, by thunder! If it don’t make me cold inside to think of Flint. This is one of HIS jokes, and no mistake. Him and these six was alone here; he killed ’em, every man; and this one he hauled here and laid down by compass, shiver my timbers! They’re long bones, and the hair’s been yellow. Aye, that would be Allardyce. You mind Allardyce, Tom Morgan?”

“Aye, aye,” returned Morgan; “I mind him; he owed me money, he did, and took my knife ashore with him.”

“Speaking of knives,” said another, “why don’t we find his’n lying round? Flint warn’t the man to pick a seaman’s pocket; and the birds, I guess, would leave it be.”

“By the powers, and that’s true!” cried Silver.

“There ain’t a thing left here,” said Merry, still feeling round among the bones; “not a copper doit nor a baccy box. It don’t look nat’ral to me.”

“No, by gum, it don’t,” agreed Silver; “not nat’ral, nor not nice, says you. Great guns! Messmates, but if Flint was living, this would be a hot spot for you and me. Six they were, and six are we; and bones is what they are now.”

“I saw him dead with these here deadlights,” said Morgan. “Billy took me in. There he laid, with penny– pieces on his eyes.”