“Now,” pursued the captain, “between those two men cast away there arose a mystery concerning the round sum of five hundred pound.”

Again Tregarthen started, changing colour. Again the captain said, “What’s the matter?”

As Tregarthen only answered, “Please to go on,” the captain recounted, very tersely and plainly, the nature of Clissold’s wanderings on the barren island, as he had condensed them in his mind from the seafaring man. Tregarthen became greatly agitated during this recital, and at length exclaimed,—

“Clissold was the man who ruined me! I have suspected it for many a long year, and now I know it.”

“And how,” said the captain, drawing his chair still closer to Tregarthen, and clapping his hand upon his shoulder,—“how may you know it?”

“When we were fellow-clerks,” replied Tregarthen, “in that London house, it was one of my duties to enter daily in a certain book an account of the sums received that day by the firm, and afterward paid into the bankers’. One memorable day,—a Wednesday, the black day of my life,—among the sums I so entered was one of five hundred pounds.”

“I begin to make it out,” said the captain. “Yes?”

“It was one of Clissold’s duties to copy from this entry a memorandum of the sums which the clerk employed to go to the bankers’ paid in there. It was my duty to hand the money to Clissold; it was Clissold’s to hand it to the clerk, with that memorandum of his writing. On that Wednesday I entered a sum of five hundred pounds received. I handed that sum, as I handed the other sums in the day’s entry, to Clissold. I was absolutely certain of it at the time; I have been absolutely certain of it ever since. A sum of five hundred pounds was afterward found by the house to have been that day wanting from the bag, from Clissold’s memorandum, and from the entries in my book. Clissold, being questioned, stood upon his perfect clearness in the matter, and emphatically declared that he asked no better than to be tested by ‘Tregarthen’s book.’ My book was examined, and the entry of five hundred pounds was not there.”

“How not there,” said the captain, “when you made it yourself?”

Tregarthen continued:—