Presently Nattie felt his curiosity aroused. What could be the man's object? Was it theft of valuable silks or deliberate incendiarism? That the fellow had a certain destination in view was made evident by his actions.
During the day the place was lighted by large glazed windows at the ends and on each side, but at night these were closed with iron shutters. In the roof were several long skylights, and through them an occasional glare came from the lightning, which still fitfully shot athwart the sky.
It was by the aid of one of these that the lad finally saw the intruder halt near a pile of tea chests. The flash lasted only an instant, but it brought out in clear relief the attenuated figure of the scoundrel. He was standing within reach of a number of boxes packed ready for shipment on the morrow.
They were wrapped in straw matting, and nearby was a little heap of the same material to be used on other chests. It was highly inflammable. This fact recurred to the lad with startling significance, and he involuntarily hurried forward.
Before he could realize his mistake he was within a step of Round. A slight cough from the latter caused Nattie to abruptly check himself. With a gasp of excitement he shrank back, and slipped behind a large bale of silks.
The next moment a blinding flash of lightning revealed the interior of the warehouse. Before it died away the plucky lad peered forth, but only to find that a change had taken place in affairs. The ex-bookkeeper was not in sight.
It was an unwelcome discovery, to say the least. With the enemy in view, it was easy to keep track of his intentions. Now he might be retreating to any part of the vast "go-down" where in temporary security he could start a conflagration at his leisure.
"I must find him at all hazards," muttered Nattie, somewhat discomfited. "Why didn't I bring matters to a point in the office? or why didn't I strike him down while I had the chance a moment ago? I'll not fool any more."
Grasping the iron lantern in readiness for instant use, he slipped forward step by step. At every yard he paused and listened intently. The silence was both oppressive and ominous. He would have given a great deal if even a rustle or a sigh had reached his ears.