We all breathed a sigh of relief.
"Well, it is still there!" exclaimed Martin, pointing at the show-case, with a forced laugh.
Suddenly came a rending and crashing sound. It seemed as if the very floor on which we stood was giving way.
The show-case, with all its priceless contents, went smashing down into the cellar below.
The flooring beneath the case had been cut through!
All crowded forward, gazing at the black yawning cavern. A moment we hesitated, then gingerly craned our necks over the edge.
Down below, three men, covered with linen dusters and their faces hidden by masks, had knocked the props away from the ceiling of the cellar, which they had sawed almost through at their leisure, and the show case had landed eight or ten feet below, shivered into a thousand bits.
A volley of shots whizzed past us, and another. While one crook was hastily stuffing the untold wealth of jewels into a burlap bag, the others had drawn revolvers and were firing up through the hole in the floor, desperately.
Martin, his detectives, and the rest of us fell back from the edge of the chasm hastily, to keep out of range of the hail of bullets.
"Look out!" cried someone behind us, before we could recover from our first surprise and return the fire.