“I allow I ain’t in a position to enlighten you,” the millionaire returned; “get it above ground, though, and there’s a fortune in it. I guess we’ll call it ‘Mervynite,’ in honour of the professor.”

“What’s that?” the scientist asked at the mention of his name.

“Silas suggests calling this new metal ‘Mervynite,’” Wilson replied.

The professor shook his head with a laugh.

“You do me too much honour,” he said; “but now let us investigate further,” and he passed into the hall of the dead.

Here, however, none cared to remain long, and, after a brief examination of this and the next vault, which was devoted to the same purpose, they passed through the tunnel on to the pavement of the reservoir. The vastness of this work astonished them, and they would fain have explored the whole of the great cavern wherein the water was stored, but that prudence compelled them to return. They dared not leave the terrace long unguarded, lest their enemies should surprise them.

“See, you mentioned a plan, Seymour?” Mervyn remarked, as they returned to the temple; “where did you put it?”

“It’s here,” answered the baronet, producing the casket from the breast of his suit. “There are some hieroglyphics on the front; perhaps you can manage to read ’em. I must confess they’re beyond me.”

The scientist’s hand trembled as he took the parchment from its case.

Spreading it out on the temple floor, he knelt down and perused it eagerly for a few seconds. Then a glad cry broke from his lips: