“Four days’ journey from Meroe toward Arabia is a city founded by men from the Upper Nile; the site is near one of its upper sources, which still has one uniform existence. This city is situated on a forked tributary, which takes its rise from a range of high, rocky mountains, almost perpendicular on their face, from which descend two streams like cataracts, about two miles apart, and form a triangle, which holds the inner city. The outer city occupies the opposite banks on either side of the streams, which after joining, form a river of considerable size, and running some five miles, loses itself in the surrounding swamps. The cities are enclosed within two great walls, running parallel with the streams. There are also two bridges with gates, connecting the inner and outer cities; two great gates also are near the mountain ranges, connecting the outer city with the agricultural lands outside the walls. The whole area is surrounded by extensive swamps, through which a passage, known only to the initiated runs, and forms an impassible barrier to the ingress or egress of strangers.

“But there is another passage known to the priests and used by them, and this is the passage which the chart outlines beneath the third great pyramid, leading directly into the mines and giving access to the city.

“When Egypt rose in power and sent her hosts against the mother country, then did the priests close with skill and cunning this approach to the hidden city of refuge, where they finally retired, carrying with them the ancient records of Ethiopia’s greatness, and closing forever, as they thought, the riches of her marvellous mines, to the world.

“Beneath the Sphinx’ head lies the secret of the entrance, and yet not all, for the rest is graven on the sides of the cavern which will be seen when the mouth shall gape. But beware the tank to the right where dwells the sacred crocodile, still living, although centuries have rolled by and men have been gathered to the shades who once tended on his wants. And beware the fifth gallery to the right where abide the sacred serpents with jewelled crowns, for of a truth are they terrible.

“This the writer had from an aged priest whose bones lie embalmed in the third pyramid above the Sphinx.”

With this extraordinary document a chart was attached, which, while an enigma to the others, seemed to be perfectly clear to Professor Stone.

The letter ended abruptly, and the chart was a hopeless puzzle to the various eyes that gazed curiously at the straggling outlines.

“What do you make of it, Professor?” asked Reuel, who with all his knowledge, was at sea with the chart. “We have been looking for mystery, and we seem to have found it.”

“What do I make of it? Why, that we shall find the treasure and all return home rich,” replied the scholar testily.

“Rubbish!” snorted Charlie with fine scorn.