CHAPTER XII
AIRSHIP PLANS
The climb up Porcupine Hill was not made as soon as most of the boys hadhoped. Several weeks elapsed and the program that had been mapped out bythe doctor was too full for any additions. Meanwhile all the absent boysof the school returned, and the trip to Grand Canyon was taken.
Only one-fourth of the boys took this trip this year, it always beingreserved for the fourth-year, or senior, pupils. Hal Kenyon was one ofthe eleven boys who visited these wonders of the Colorado River on thisoccasion. And on his return he was so full of the delights of thescenery that Mummy Canyon and Flathead were for a time of minor interest.
But in time their old fascination returned. The cave behind thewaterfall at no time ceased to be an object of much interest to him, andhe was continually wishing that something would put it into Dr. Byrd'shead to make a thorough inspection of the cavern. And if this were done,Hal naturally hoped that he would be one of the inspectors.
Meanwhile the broken bones of Aviator Miles mended rapidly. As soon asit was deemed safe, he was permitted to leave his bed and hobble aroundon crutches, his leg still in a cast, however. From the time of hisfirst exit from the Hospital, he was an object of much interest to theboys. They gathered around him at every opportunity and begged forstories of his experiences, and he usually had something of absorbinginterest to tell.
He told them that he had been among the Rockies from YellowstoneNational Park to the Grand Canyon for two months before his accident, andhe exhibited before their eager eyes his collection of stones and quartzthat Hal had discovered in the waterfall cave.
"But they're not all here," he remarked as he poured them out on anewspaper that he had spread on the lawn in front of Dr. Byrd's home. Hewas seated on the grass while a score of boys stood around in eagerattention.
"Where are the others?" inquired Fes.
"I don't know," replied the aviator slowly. "There were six pretty fairsized gold nuggets in the bag when I fell; or they were there a fewhours before, and I don't see how they could have disappeared."
"I didn't see any when I opened the bag in the cave."
Hal volunteered this information, but the sentence was finished with adifferent tone of voice from the tone at the beginning. In the midst ofhis statement he suddenly realized the importance to him of thedisappearance of the nuggets, and a lump arose in his throat, so that hecould hardly finish what he started to say.
Everybody noticed the change in Kenyon's voice, and all looked at him asif for an explanation. Conscious of his seeming self-betrayal and of theinquiring glances directed at him, he blushed with confusion. Theaviator suspected at once that these were signs of guilt.
But Hal knew better and flashed back a look of scorn and indignation athis silent accusers. Recovering his natural tone, he said in a cool,measured voice:
"I don't know what became of those nuggets. They certainly were not inthe bag when I opened it."
Most of the boys believed in Hal and were convinced by this sturdystatement. Mr. Miles, however, was not convinced, although he did notlike to hold any suspicion against a boy who had impressed him so well.But he saw nothing to be gained by embarrassing Kenyon at present.
"Well," he said; "this isn't the only mystery connected with the affair.I'm just as curious to know how the bag ever got into that cave."
"You think somebody put it there?" Hal inquired.
"Being an invalid and unable to get around very conveniently, I haven'tbeen able to inspect the place yet. But from all descriptions received,I'm in need of more evidence to convince me that it bounced in there byaccident. In the first place, I'm dead certain it fell to the groundwith the aeroplane."
"Maybe the strut it was tied to was what broke and made you fall,"suggested Hal.
"It wasn't a strut at all that broke. It was a couple of stay wires. Thestruts couldn't break under any but the most extraordinarycircumstances."
"Are you goin' to fix up your aeroplane again, or get a new one?" askedHugh Messinger.
"Oh, nothing can be done with that pile of junk. You boys might as wellburn the wood and tote the steel framework into your blacksmith shop."
"Are you going to quit flying?" asked Byron Bowler.
Mr. Miles looked with keen amusement at the last questioner and repliedwith a wink:
"Do I look like a quitter?"
He surely didn't, although forced to stop for several weeks with somebroken bones. Miles was a sturdy, determined-looking man, with firm-setjaw and clear bright eye that gave no hint of hesitation.
"What you going to do? Buy another airship?" Byron persisted.
"I've bought one already."
"You have!" eagerly exclaimed several of the boys. "Where is it?" one ofthem continued.
"It's on its way out here."
"Out here!"
This exclamation also came in chorus from half a dozen astonished BoyScouts.
"Yes," answered the crippled aviator; "it's on its way out here. But itisn't put together ready to fly. It's in the knock-down. I'm going togive you boys the job of putting it together."
"Oh!--when will it be here?" asked one enthusiastic youngster.
"In a week. Dr. Byrd and I had several talks about the matter, and he'sdecided to let you boys have the job. I won't be strong enough to domuch on it myself, but I'll be on hand and boss."
"What kind is it going to be?" asked Pickles. "Like the one you fellin?"
"Not exactly. It'll be a biplane, but a much better one than the Ozone."
"What's the Ozone?" inquired Ferdinand.
"That's the name of the biplane I fell in. The new one will carry twopassengers besides the operator."
"Oh, ain't that fine!" cried Glen Juza. "It's just swell. And can we allhave a ride?"
"Oh-ho," laughed Miles. "I thought it would come to that. But it reallyisn't up to me to decide. I might say yes, and Dr. Byrd might say no. Heprobably would."
Disappointed looks and expressions followed this prophecy. The doctor'spupils could just as well have predicted such an outlook without theassistance of older heads, but they were naturally optimistic.
"But don't be discouraged, boys," added the aviator. "Your time willcome sooner or later. Maybe you'll be afraid to go up with me when yousee the airship all finished. It--"
"Yes we will!" "I wouldn't!" "You don't know me!" were some of the braveinterruptions.
"It won't look very safe," was the aviator's warning. "Pretty thin andflimsy."
"I don't care; I'll go up in anything you will," cried Frank Bowler, whohad listened to the conversation in silence up to this time. He wasgradually regaining his former nerve and bluster, but his voice did notyet have a natural ring.
"What will the new aeroplane look like?" asked Hal Kenyon.
Most of the boys by this time had spent their enthusiasm and settleddown to quieter attention. Seated on the grass, they waited eagerly forthe answer to Kenyon's question. By this time a good crowd of boys hadjoined the audience.
"I may as well give you your first lesson in aeroplane building rightnow," began the aviator, shifting slightly to ease his crippled limb."First, do you all know what a biplane is?"
"It's an airship," said one.
"No, it's an aeroplane," corrected another.
"What's the difference between a biplane and a monoplane?" interposedMr. Miles.
This was a puzzler for most of the boys. After several had answered andflunked, Hal Kenyon spoke up:
"A monoplane has one plane, and a biplane has two planes."
"What is a plane?"
"A flat surface."
"Good," complimented Mr. Miles. "You know a little geometry. The planesare the wings of an aeroplane.
"Now, the aeroplane will be built on this plan: The part that willinterest you boys most will be the cabin. As I said, it will carry twopassengers comfortably besides the operator. And it is to be so arrangedwith an automatically shifting weig
ht that these passengers can moveabout without disturbing the balance of the ship.
"This will really be an airship. The ordinary aeroplane is not entitledto such a name, for it is merely a skeleton without any body. Thisvessel will have a real body, made mostly of aluminum, except the glasswindows and ports. The front, or prow, will be blunt in accord with thelatest ideas of air friction. The front and rear of this cabin will besupplied with flexible slides that may be slipped around to the sides,leaving the front and rear open. This will remove practically allresistance, except for perpendicular rods six inches apart, giving thecabin something of the appearance of a cage.
"In cold weather, or in high altitudes, these slides can be closed andthe cabin warmed with a small alcohol stove. Otherwise there will belittle remarkable about the ship. You will all be interested in suchdetails as the motor and the steering and weather apparatus. You willlearn all about the altitude barometer and the anemometer, or speedmeasurer. In other words, you will absorb a lot of information on airnavigation while putting this airship together."
"How about that weight?" Hal questioned as the instructor in aeronauticspaused. "You say it shifts automatically. Can you explain that so we canunderstand how it keeps the ship from turning over?"
"I'll try. The floor is of a flexible material. As one walks here andthere, it is pressed downward and by means of a delicate mechanicaldevice, shifts a weight on a rod. The shifting of this weight alters theangle of the ailerons at the ends of the wings and prevents the machinefrom tipping out of balance. Understand?"
Blank looks on every face before him advised Mr. Miles that he had beentoo technical for the boys, so he added:
"You'll understand easily as you advance in the construction of thevessel. But possibly this may give you a hint of what I am driving at:Changing the angles of the ailerons has the same effect in anup-and-down direction, as turning a boat's rudder has from side toside."
Still few of the boys understood what he meant, although Hal Kenyon andone or two others believed they did. Later, when he found anopportunity, Hal, with pencil and paper, made some drawings and studiedover them and altered them until he was certain that he had a clear ideaof the plan. Then he took his last drawing to Mr. Miles and explained itto him, and the aviator told him he was right.