"Hoots! There's going to be a storm before long!" exclaimed Sandy suddenly, as a vivid flash of lightning ripped the sky.
It was the same that Tom was observing at that instant as he embarked on his perilous mission.
The flash, short as it had been, had sufficed to show Jack the true peril of their path. The stairs were not more than eighteen inches wide. At one time there may have been a balustrade on the outer edge. But, if this had ever been the case, it had vanished now. Jack felt an odd sinking at the pit of his stomach, as he saw the ground beneath them illumined for that brief molecule of time. It looked fearfully far off. He could not help picturing in his imagination the fatal results of a misstep.
But Sandy had none of these qualms of fear. He went right ahead, exercising due caution, it is true. But his mind was more busy with the real peril of discovery than with the thought that a false step might plunge its maker down to death.
He was proceeding thus, step by step, when he halted abruptly. His outstretched foot had encountered vacancy.
"Hoots! What's this?" thought Sandy.
At that instant came another flash. What it revealed made even the stout-hearted Scotch lad quiver and sicken for an instant.
No steps lay beyond his foot.
Instead, there was a dark void where several of the stones had fallen out. One step more, and Sandy would have been dashed to the earth, he did not know how many feet below. Perspiration broke out in tiny pin-points all over him.
What were they going to do?