But now the ruffians who were coming furiously up the stairs demanded his attention.
"Halt!" he shouted. "Stop where you are, or I shall open fire on you!"
He could see them, and he saw the foremost lift his hand. Then there was a burst of flame before Frank's eyes, and he staggered backward, feeling a bullet near his cheek.
Not till that moment did he realize what a trap he was in, and how desperate was his situation.
"It is a fight for life!" he muttered, as he lifted his revolver.
The smell of burned powder was in his nostrils, the fire of battle gleamed from his eyes.
The weapon in Frank's hand spoke again, and once more he found his game, for the leading ruffian, having almost reached the head of the stairs, flung up his arms, with a gurgling sound, and toppled backward upon those who were following.
Down the stairs they all tumbled, falling in a heap at the bottom, where they struggled, squirmed, and shouted.
"So far everything is very serene!" half laughed the daring boy. "This has turned out to be a real lively night."
Frank was a lad who never deliberately sought danger for danger's sake, but when his blood was aroused, he entirely forgot to be afraid, and he felt a wild thrill of joy when in the greatest peril.