David was short and fat, but he proved an agile walker, and the darkness of the night was no hindrance to his way. He led his companions through many black alleys, turning first one way and then another, until he finally paused before a small stone house that stood vacant and delapidated. Drawing a key from his pocket he unlocked the door and drew the others into a damp and close-smelling room.

A moment later he struck a match and lighted a candle.

“Now ve can see vhere ve go,” he said, complacently.

The Americans looked around them with some curiosity. Although doubtless of considerable age the house seemed never to have been finished inside, or even occupied as a place of abode. Bits of the building blocks were yet scattered over the earthen floor.

“Vonce, in de time of Keedar Khan,” said David, “a young kaid built dis house ant made a tunnel unner de grount to de khan’s harem, vhere hiss sveetheardt vas liffing. When she vas nod combing de vhiskers of de Khan she vas hugging de young kaid; ant vhen she vas nod hugging him she vas combing de Khan’s vhiskers. Id vas very nice arrangements. Bud von night de Khan called on de female vhen he vas nod expected, ant he cut de young kaid ant de girl both into slices before he enquired how de feller got into de harem. Id vas all very careless of de Khan; but he had a bad temper. So de tunnel vas neffer used again until I find it oudt a couple year ago. I buy de place cheap because de mans vot owned it neffer looked to find a tunnel. Ant now id iss very handy for us, ant very cheap for a t’ousant fillibees. Come—I show you.”

Chuckling softly, the Jew led the way through a narrow passage and down a few steps into a sort of underground cellar at the rear. Here, in one corner, a flagstone stood on edge, disclosing another flight of steps. Down these David proceeded without hesitation, the Americans following closely at his heels. Then came a damp, ill-smelling tunnel, so low that only David could traverse it without bending down. The candle lighted the way only a few steps in advance, and numerous rats scurried from their path as they slowly advanced.

It seemed like a never-ending journey; but, just as the Colonel was about to protest, the passage suddenly widened and grew higher, and the light of the candle fell upon a cedar panel let into the wall before them.

“Have you the key, David?” whispered the doctor.

“Id iss no key; id iss a spring,” replied the Jew. “Vod time iss id now?”

The Colonel looked at his watch. It was nearly midnight.