"Get off there, Koku!"  
"Stand up!"
 
"Run!"
 
"Get out of the way! That's going up!"
 
Thus cried Tom and his friends to the big, good-natured, but somewhat stupid, giant who had sat down in the dangerous spot. Koku looked toward the hut, in front of which the young inventor and the others stood, waving their hands to him and shouting.
 
"Get up! Get up!" cried Tom, frantically. The powder is going off, Koku!"
 
"Can't you stop it?" asked Job Titus.
 
"No!" answered Tom. "The electric current has already ignited the charge. Only that it's slow-burning it would have been fired long ago. Get up, Koku!"
 
But the giant did not seem to understand. He waved his hand in friendly greeting to Tom and the others, who dared not approach closer to warn him, for the explosion would occur any second now.
 
Then Mr. Damon had an inspiration.
 
"Call him to come to you, Tom!" shouted the odd man. "He always comes to you in a hurry, you know. Call him!"
 
Tom acted on the suggestion at once.
 
"Here, Koku!" he cried. "Come here, I want you! Kelos!"
 
This last was a word in the giant's own language, meaning "hurry." And Koku knew when Tom used that word that there was need of haste. So, though he had sat down, evidently to take his ease after a long tramp through the woods, Koku sprang up to obey his master's bidding.
 
And, as he did so, something happened. The first spark from the fuse, ignited by the electric current, had reached the slow-burning powder. There was a crackle of flame, and a dull rumble. Koku sprang up from the big stone as though shot. What he saw and heard must have alarmed him, for he gave a mighty jump and started to run, at the same time shouting:
 
"Me come, Master!"
 
"You'd better!" cried the young inventor.
 
Koku got away only just in time, for when he was half way between the group of his friends and the big rock, the utmost force of the explosion was felt. It was not so very loud, but the power of it made the earth tremble.
 
The rock seemed to heave itself into the air, and when it settled back it was seen to be broken up into many pieces. Koku looked back over his shoulder and gave another tremendous leap, which carried him out of the way of the flying fragments, some of which rattled on the roof of the log hut.
 
"There!" cried Tom. "I guess something happened that time! The rock is broken up finer than any like it we tried to shatter before. I think I've got the mixture just right!"
 
"Bless my handkerchief!" cried Mr. Damon. "Think of what might have happened to Koku if he had been sitting there."
 
"Well," said Tom, "he might not have been killed, for he would probably have been tossed well out of the way at the first slow explosion, but afterward—well, he might have been pretty well shaken up. He got away just in time."
 
The giant looked thoughtfully back toward the place of the experimental blast.
 
"Master, him do that?" he asked.
 
"I did," Tom replied. "But I didn't think you'd walk out of the woods, just at the wrong time, and sit down on that rock."
 
"Um," murmured the giant. "Koku—he—he—Oh, by golly!" he yelled. And then, as if realizing what he had escaped, and being incapable of expressing it, the giant with a yell ran into the tunnel and stayed there for some time.
 
The experiment was pronounced a great success and, now that Tom had discovered the right kind of explosive to rend the very hard rock, he proceeded to have it made in sufficiently large quantities to be used in the tunnel.
 
"We'll have to hustle," said Job Titus. "We haven't much of our contract time left, and I have reason to believe the ............