It seemed to them then that the rats were two or, three deep on the floor. There appeared to be hundreds—thousands of them. They circled around the boys, becoming bolder every moment. They nipped at the rubber boots and left the marks of their teeth on the tough uppers.
"Now, boys," Tommy yelled, as they drew their automatics and leveled them over the wall, "shoot to kill! This is no Sunday School picnic! And while we're shooting, boys, you back up to this wall, and see if you can't work your way to the top. If you can get up here, we can manage to displace enough slate to let you through."
The boys fired volley after volley, but the rats came on viciously.
CHAPTER XV
A STICK OF DYNAMITE
By this time Jimmie and Dick had their automatics out and were firing into the horde of rats. They killed the rodents by the score, yet for every one slaughtered a dozen seemed to appear.
Presently the chamber became so full of powder smoke, the air so stifling, that the lads were obliged to cease firing.
"Work your way up this wall," Tommy cried out to the lads as he heard them panting below. "Work your way up so we can catch hold of you, and you'll soon be out of that mess!"
"There's a dozen rats hanging to my boot!" cried Dick.
"And mine, too!" declared Jimmie.