The moon was up; there were no clouds now, but there was not a very strong light, because the moon was on the wane.  It was one of those nights during which an imperceptible vapour arises, and renders the moon somewhat obscure, or, at least, it robs the earth of her rays; and then there were shadows cast by the moon, yet they grew fainter, and those cast upon the floor of the apartment were less distinct than at first.

There seemed scarce a breath of air stirring; everything was quiet and still; no motion—­no sound, save that of the breathing of the two who sat in that mysterious apartment, who gazed alternately round the place, and then in each other’s countenances.  Suddenly, the silence of the night was disturbed by a very slight, but distinct noise, which struck upon them with peculiar distinctness; it was a gentle tap, tap, at the window, as if some one was doing it with their fingernail.

They gazed on each other, for some moments, in amazement, and then at the window, but they saw nothing; and yet, had there been anything, they must have seen it, but there was not even a shadow.

“Well,” said Mr. Chillingworth, after he had listened to the tap, tap, several times, without being able to find out or imagine what it could arise from, “what on earth can it be?”

“Don’t know,” said Jack, very composedly, squinting up at the window.  “Can’t see anything.”

“Well, but it must be something,” persisted Mr. Chillingworth; “it must be something.”

“I dare say it is; but I don’t see anything.  I can’t think what it can be, unless—­”

“Unless what?  Speak out,” said the doctor, impatiently.

“Why, unless it is Davy Jones himself, tapping with his long finger-nails, a-telling us as how we’ve been too long already here.”

“Then, I presume, we may as well go; and yet I am more disposed to deem it some device of the enemy to dislodge us from this place, for the purpose of enabling them to effect some nefarious scheme or other they have afloat.”

“It may be, and is, I dare say, a do of some sort or other,” said Jack; “but what’ can it be?”

“There it is again,” said the doctor; “don’t you hear it?  I can, as plain as I can hear myself.”

“Yes,” said Jack; “I can hear it plain enough, and can see it, too; and that is more.  Yes, yes, I can tell all about it plain enough.”

“You can?  Well, then, shew me,” said the doctor, as he strode up to the window, before which Jack was standing gazing upon one particular spot of the shattered window with much earnestness.

“Where is it?”

“Look there,” said Jack, pointing with his finger to a particular spot, to which the doctor directed his attention, expecting to see a long, skinny hand tapping against the glass; but he saw nothing.

“Where is it?”

“Do you see that twig of ivy, or something of the sort?” inquired Jack.

“Yes, I do.”