SO far as sleeping in a hammock suspended a dozen feet above ground was concerned, Bunk’s attempt was as much a failure as his effort to rest among the limbs of the oak on the previous night. In disgust he gave it up, and yanking the blanket free went back to the cavern and again slept without disturbance. The weather continued so mild that the covering gave him all the protection he needed.  
When Professor Morgan made his appearance in the morning, not quite as early as before, Bunk saw he was not in such buoyant spirits as on his last call. Something had gone wrong. He made no replies to the lad’s questions, but when about to leave him for the day, explained:
 
“Things haven’t come out as I anticipated; I shall have to go to Albany again to get a new chemical; the last was not pure; do you understand?”
 
“Yas, sir.”
 
“You don’t understand a word I said to you,” snorted the man; “why do you pretend you do?”
 
[248]“Yas, sir.”
 
With an angry grunt the aviator mounted his seat, started the uplifter revolving and sailed away without another word.
 
Several days now passed so similar in all respects that it is not worth while to dwell upon them. The Professor remained glum and sour and Bunk held him in too great awe to repeat any questions after his first curt snubbing. He made his sleeping quarters in the cavern, ate and wandered through the neighborhood, watching people at a distance and always keeping out of their sight. Had he possessed a field glass like Harvey Hamilton, he would have made some discoveries that would have interested and alarmed him.
 
We come now to the day of the disastrous search made by the Hamilton brothers. Bunk was sitting at the mouth of the cavern and beginning to feel drowsy when his nerves were set tingling by the whistled signal of the young man, who had almost come upon him. Had Dick refrained from giving that warning he would have been face to face with Bunk within the following five minutes.
 
“Dat’s him!” gasped the negro, scooting behind the cavern and among the undergrowth, where he crouched low.
 
[249]He not only heard every signal, but caught a glimpse of the young man. Had it been Harvey whom he saw he probably would have gone forward in response to the calls, but he dared not let the elder brother see him.
 
“I’d doot,” muttered Bunk, whose conscience reproved him, “if I could be sure he wouldn’t butt in and make trouble.”
 
One fact lifted the spirits of Bunk to the highest notch. That morning Professor Morgan exultingly told him that he had attained complete success at last. The new chemical had done its work perfectly; the last obstacle had been overcome, and the start for distant Africa would be made the next day without fail. It was this announcement which caused the youth to guard against discovery by his friend. Of course he did not dream that Harvey Hamilton was in the vicinity.
 
Bunk was in such a fluster over the knowledge that his dismal days in this mountain retreat were ended that he slept little. This was his last night in the cave and the wonderful voyage was to begin on the morrow.
 
Upon what trivial incidents do the most important events often turn! Professor Morgan told the truth when he asserted that he had reached the[250] end of his experimentation. He had solved the magical combination of chemical agents by which the supply of fuel for his helicopter would serve for more than two days without renewal. Having done this, all that remained was to finish his preparations for leaving the continent and voyaging over the Atlantic. His machine worked so superbly that he had no fear of any storm he might encounter, though he wisely decided to study weather probabilities before making his venture. Repeated tests convinced him that an average speed of eighty miles was easy to maintain. This would require a trifle less than thirty-three hours to go from Quebec to Liverpool, his intention from the first being to start from the former city.
 
The change he made in his programme was this: instead of leaving Quebec, he would make his starting point on the New Jersey coast, not far below Sandy Hook, with his destination the island of St. Vincent, of the Cape Verde group, off the coast of Africa. This route is three hundred miles longer than the other, but as he viewed it the fact was not worth considering because of the new fuel he had invented. It was not far from St. Vincent to the African coast, and he preferred not to land in England because of the excitement his feat would cause.
 
[251]So long as his purpose was to depart from Quebec, he intended to lay in the necessary stock of provisions in that city, deferring the work until the last moment. But this was sure to bring unpleasant notoriety, and he now saw an easy escape from it. No large amount of supplies would be needed and he could procure them at the Washington Hotel in Dawson. As for himself, he did not mind fasting for a couple of days, but he knew how it was with his assistant. He therefore proceeded to stock up in the little country town, because of which his usual morning call upon Bohunkus Johnson was delayed, and it was that same delay which gave the necessary time for the happening of more than one important event.
 
Had Bunk not been impatient over the tardiness in the return of Professor Morgan, he would have paid attention to the two persons in the canoe at the end of the lake. He would have seen them leave the craft and disappear among the trees and undergrowth that lined the sheet of water, but he noted nothing of the kind. It is doubtful which emotion was the stronger within him,—the desire for satisfying his craving for food, or his eagerness to start upon the aerial voyage to the Dark Continent. He took his station in front of the cavern and scanned the heavens to the south,[252] wondering what could keep the aviator away so long.
 
“He oughter hurry up, ’cause it am a long way and we’ve waited so many days dat dere ain’t no sense ob waiting longer.”
 
Hark! What was that which fell upon his ear? It sounded like the whistle which he had heard so many times when he and Harvey or Dick Hamilton were calling to each other.
 
“Can’t be Harv,” he whispered, “’cause he am ten thousand miles away; must be dat Dick is poking round here agin.”
 
This time there was no mistake. The signal was so clear and sharp that Bunk turned sharply and stared at the point whence it came. He was struck speechless when he saw the smiling Harvey walk toward him.
 
“Hello, Bunk! I’m glad to see you.”
 
For one moment the lad stood transfixed, and then overwhelmed by the threatened calamity, as it seemed to him, he wheeled and made a d............