“Because,” replied he, “in connection with their religious rites the aboriginals habitually made offerings to the deities of the lake in the form of gold dust, golden images, and emeralds, the most famous emerald mines of the world being situated in the heart of Mexico. Indeed, Prescott says that this particular gem was held as sacred by the early tribes inhabiting Mexico as being the emblem of the sun, they themselves being sun-worshippers. More than that, their king, who was also their pontiff, was in the habit of being completely covered with gold dust so applied as to cause him to shine with great lustre like the rays of the sun. In brief, he was the real ‘El Dorado’ of whom we have heard so much and seen so little; and, as his principal religious ceremony, he was wont to perform his ablutions from a raft in the centre of the lake, until the whole of the precious metal was washed away. This accomplished, the king, and the chiefs who were with him, made a rule of throwing costly offerings into the water.”

“Better than that,” struck in the hunchback, almost with enthusiasm, “I have just been turning over an article in the South American Journal on this very subject, and I read there that the multitude of worshippers, thereupon, likewise cast in their humbler contributions in the midst of singing and dancing and to the sound of such musical instruments as were available. When the ‘bearded men’ reached the country it is stated that the Indians, to put their treasure beyond the power of the ruthless invaders, threw it into the waters of the lake to a vast value; and, indeed, an attempt was made by the Spaniards to unwater it, so as to get at the submerged accumulation of gold dust and precious stones. They were not able to reach the bottom, but succeeded in lowering the water to such an extent as to expose a portion of the margins of the lake, whence they obtained sufficient to pay to the Spanish Government one hundred and seventy thousand dollars, equivalent to three per cent, on a total recovered of five millions six hundred thousand dollars. There were also emeralds, one of which realised seventy thousand dollars in Madrid. Further progress was arrested by the sides of the cutting on the lip of the lake-cup falling in with a tremendous crash. The water poured into the mouth of an adjacent volcano, and a terrible earthquake resulted, before which the Spaniards and their Jesuit friends fled in terror. A proper record was, however, made later on of the exact position of the lake, but, as Mr Cooper-Nassington explained, it was lost.”

“And you have recovered it,” I burst out.

“That is so; but although repeated expeditions were made to the district, which is largely of volcanic origin, to discover it without the key I possess, they all failed; and as the years slipped on they grew fewer and fewer in number until, as you have heard for yourself, the whole thing has just become a will-o’-the-wisp of the manuscript hunter who, of course, has mostly grown to feel he is as likely to discover the missing documents as he is to find the title-deeds of the temple of David.

“But,” said the hunchback, suddenly changing his tone and confronting my companion with an angry look, “none of this is to the point. It is, in a way, all so much ancient history and as familiar to men like yourself, who rule Mexico through the Stock Exchange or our British Foreign Office, as your alphabet. What I want to know is: What business is it of yours what I have bought and what I have discovered? You have no share in this find. You have no right to information. By what right do you come here demanding to know what I have learned, and shall learn, with infinite patience, expense, and labour?”

“All that in good time, my dear sir,” calmly returned Cooper-Nassington. “For the present it must be sufficient for you that I have a very real and vital stake in what you have found, and you had better treat me well over the business when I come to you again after you have deciphered the manuscripts, or you’ll live to regret the day I was born.”

For a second the two men stood glaring at each other in angry defiance, but again I saw that the millionaire won. Whatever was the mysterious hold he had over the hunchback there was no doubt but that it was a very potent and a very effective one, and that, however much Zouche might kick and threaten, in the end he was bound to come to the other’s heel.

“All right. Come to me in a fortnight’s time,” he growled, “and I’ll see then what can be done. Don’t fancy, though, that this business is simply fitting out a yacht with a party of Cornish miners and engineers and going to take possession of the loot.”

“I don’t,” said the Member of Parliament coolly; “there are the Jesuits to reckon with.”

“Yes; but that’s not the worst,” retorted Zouche; “there are others.”