Dinosaurs & A Dirigible (37 page)

While Carl finished his business with the farm, Professor Erlenwanger had poured the twenty cans of kerosene into the funnel-mouthed nozzle he had extended from the rear of the gondola. Molly was stacking the empty cans up against the wall of the barn for the Gudeints to use or return for credit. She nodded to Carl as she entered the gondola and sat primly at a bank of sixteen levers, each with a gauge above it. The Professor himself stood at a helm like that of a ship. The spokes appeared to have additional control switches built into them. To the right front of the helm, along the glazed forward bulkhead, was a double bank of waist-high levers. The control room was no more spacious than the garret bedrooms Fred and George each had to themselves, but it was only the front third of the gondola.

“Carl, if you’ll take a seat at the other console,” Erlenwanger said, gesturing to the chair just aft of the gondola’s door. “Soon I’ll teach you how to operate the motor controls yourself, but now, in the interests of a prompt departure . . .”

Carl nodded and sat as directed, eyeing the north field where his father and eldest brother were haying. The Professor leaned over him and threw a switch. “Since we ride on hydrogen,” he said cryptically, “it’s no difficulty to bleed some into the injectors in place of ether for starting . . .” He flipped a second switch. Something whined briefly and the motor grunted to life. It sank quickly into a hum that was felt but not really heard in the forward compartment. Erlenwanger listened for a moment, then said, “Very good.” He pointed to a knob with a milled rim. “When I direct you to, Carl, please turn this knob a quarter turn clockwise. It engages the airscrew, which we don’t want to do until we have a little altitude, do we?” He smiled brightly at both his crew members. “Not pointed at the house as we are, that is.”

Erlenwanger returned to the helm. “There doesn’t seem to be enough wind today to require us to make an immediate jump for altitude. I’m always concerned about that, for fear that a line stoppage will lift us asymmetrically; so Molly, if you will fill tanks five and eight.”

The girl quickly threw two levers. The gauges above them began to rise as the metal fabric trembled to a mild hissing. The older man said, “Each of the sixteen tanks is split in two by a movable partition. The partition acts as a piston when the pressure on one side of it becomes higher than that on the other side. One and sixteen, Molly; then two and fifteen,” the Professor continued.

Molly worked the requested pairs of switches, pausing after the first to make sure the operation was smooth. She glanced at Carl over her shoulder and said, “What he means is, the gas pushes air out of the tanks when we want to go up, and the air pushes the gas out when we want to go down.”

Erlenwanger turned and blinked. “That’s very good, Molly. I’m afraid I often talk more than I communicate. Though air is a gas as well as hydrogen, of course . . . still. If you will fill the next three pairs in order, please.”

The hiss of gas was a living sound now. The gondola was rocking like a rubber ball on the surface of a lake, not lifting off the ground but responsive to every ripple in the air. “I think we’re about ready,” said Erlenwanger. “Carl, I’ll give you the word in a moment. Molly, fill the central tanks.”

The gondola shuddered. The pattern of light through the side windows shifted as they swung beneath the lifting hull. The ship was rising at a walking pace, drifting toward the barn and rotating about thirty degrees in the grip of the mild breeze. “Carl, engage the screw,” said the Professor. The boy obeyed, his hand so tight on the knurled brass that it did not slip despite its sweatiness. Erlenwanger rocked his helm forward on its post as he felt the propeller bite. The side-slipping continued but was lost in the greater surge of the airship’s forward motion. They were still rising. Looking through the windows beyond Molly, Carl could see the hay-cutting rig at the point of the bright swathe cut from the darker green of the north field. The horses were the size of Chihuahuas. The two men in the field shaded their eyes with their hands as they stared at the shimmering oval in their sky. They were too far away for Carl to have recognized them by sight alone. They did not wave. After a moment, as the field and his former life slipped behind at locomotive speed, Carl did.

Professor Erlenwanger released the helm and stepped over to where Molly sat. The airship continued moving smoothly at better than twenty miles an hour. The rolling land was now almost three thousand feet below. “We’re a little higher than I care to be without a reason,” Erlenwanger said. “Probably because the Sun is so bright. Molly, would you care to balance all the tanks at seventy-five percent? That should bring us down about a thousand feet. Besides, I prefer to have some pressure in all tanks rather than flying with some voided and others full.”

Using the bar that fitted the full length of her panel, Molly slid the fourteen open switches down to three-quarters. Simultaneously, she slid the other pair up to the bar with her free hand. The airship lurched, steadied, and continued to skim through the air. It was dropping noticeably, a sensation less like diving into a pond than it was like a toboggan ride down Indian Mound Hill. Erlenwanger studied the line of silver in the etched glass column above his helm. His lips pursed and he touched another display to the side of the column. “We aren’t getting the lift we should out of the forward tanks,” he said to no one in particular, “though we seem to have leveled off satisfactorily. Moisture in the tanks, I suppose. We’ll have to empty them in the near future.”

“Where do you buy your hydrogen, Professor?” Carl asked, staring down through the transparent quarter-panels of the gondola. He had seen fields from atop the sharp bluffs which wrinkled eastern Iowa, but there was something marvelous in watching solid ground flow by below like a river choked with debris.

“I manufacture it from water,” the older man said. “Our motor powers an electrical generator. When it is necessary to fill a hydrogen tank, I simply run a current through a container of water and collect the separated hydrogen atoms above the cathode.”

Warming to his subject—though little of what he had already stated made sense to Carl—Erlenwanger continued, “You see, that is where some theorists go wrong in asserting that helium is safer than hydrogen because it cannot be ignited. What they ignore is the
cost
of helium. The only way to keep an airship safe over a long period is to clear it of the condensate that otherwise—and inevitably—loads it down to the point that a storm smashes it. And the only sure way to clear the condensate is to vent your tanks and dry them periodically. Helium is rare and far too expensive to be ‘wasted’ in that fashion—so lives will be wasted instead. Hydrogen is cheap and can be manufactured anywhere, either from acid and iron filings or—much more practically—by electrolysis, as I do.”

The Professor shook his head. “It will be a long time, if ever, that men will stop sending other men to their deaths by ignoring the practical realities which make their theories specious. We should not enshrine human realities, my young friends, whether economic or otherwise; but neither should we expect them to disappear because we ignore them.”

Erlenwanger caught himself. He smiled wryly at both his companions. Their eyes were focused at about the level of his stick-pin in determined efforts not to look bored. “Well,” he said, “I think it’s far more important to teach Carl the rudiments of
The Enterprise
than it is for me to go on about things that only time will change. Molly, would you care to show our new recruit how your panel functions? I can listen and make suggestions if it seems useful.”

The older man sat in Carl’s chair, watching as Carl moved over beside Molly. The airship flew on at a steady pace, over farms and wooded hilltops, water courses in which cattle stood to their bellies, and occasionally a small town in a web of dry, gray roads. Throughout the afternoon, Carl learned the workings of the machine which was less wonderful to him than was the girl at whose side he sat. The levers of the starboard panel controlled the flow of hydrogen between the buoyancy tanks and the storage reservoir in the keel. “It’s held in a liquid state,” the Professor interjected, “and the insulation of the reservoir is an improvement—a very great improvement—over previous applications of Dewar’s principles.”

Understanding the technique of raising or lowering the airship was easy, but executing the technique was another matter again. Carl made several attempts to modify the craft’s buoyancy at Erlenwanger’s direction. Each experiment sent
The Enterprise
staggering through the air at an unexpected angle or altitude. At the end of the session, the boy had a fair grasp of what the duties entailed—and he had enormous respect for the girl who performed them.

“How long have you been practicing this?” asked Carl as Molly brought them back to level flight at two thousand feet following his own series of unintentional aerobatics.

“Well, about four days, now,” said the girl, glancing over at the Professor for confirmation. “I’ve been doing it ever since the Professor—oh dear.” She broke off in indecipherable confusion, blushing and looking away from both men. “I’m sorry, I didn’t mean to—”

“Nor did you, my dear,” Professor Erlenwanger said calmly. “And in any case, I intended to explain the situation to Carl at once anyway. You see,” he continued, turning to the boy, “Molly is no more my daughter than you are my son—which is how I intend to describe you to those whom we meet on our travels. I assure you, there is no improper conduct involved in Molly’s accompanying me, any more than there would be had she been a blood relation. However, so as not to offend those persons whom we meet, I determined to tell an untruth—a lie, if you will. I dislike lying, and I will not lie to another’s harm, but the truth is less important than the fellowship of many humans meeting without enmity.”

Carl licked his lips. “What did your real parents say?” he asked.

Molly looked down. “I haven’t real parents,” she said softly.

“Molly was a foundling,” Erlenwanger said. “She was in service at a house in Boston until she refused a—an improper demand by the master of the house. She was turned out of her place the day before I met her.”

“I never told you that!” the girl blurted.

“Nor do I mention it to embarrass you, my dear,” Erlenwanger said. “We will be together for some days and in close proximity, however, and I think it necessary that Carl understand your situation as clearly as you do his.”

They proceeded through the airship’s two other stations. The motor-starting drill appeared to be ridiculously simple: depress the hydrogen feed for three or four seconds, release it, and flip the starter switch. Shut-down was even more basic, a third switch that “shut off the injectors,” which meant nothing at all to Carl but obviously seemed an adequate explanation to the Professor.

There were a dozen circular gauges above the switch panel. “While the motor is running,” Erlenwanger said with a gesture, “the pointers should all be in the green zone. If one of the pointers falls into the red or rises to the white, tell me. Nothing very dreadful is going to happen without our hearing it, though, so don’t feel you have to stare at the dials.”

“It isn’t really very simple, is it?” Carl said thoughtfully.

“Umm?” said Erlenwanger, pausing in mid-step as he moved to the helm.

“You make it look easier than running a feed mill,” Carl went on. “Maybe it is, too. But it’s not simple, it’s just simple to run. Being able to milk a cow don’t mean you could build a cow yourself.”

“That’s true, of course,” the older man agreed with a pleased expression. “I’m really delighted to have met you, Carl. One has an emotional tendency to equate ignorance with stupidity, which meeting you—meeting you both”—and his hand spread toward Molly—“has dispelled.

“But to answer your implied question, Carl,
The Enterprise
is unique in the world. However, if she were examined at length by today’s finest scientists and engineers, they would find only her workmanship to be exceptional. Others—many others today—have all the ‘secrets’ I have embodied in the Erlenwanger Directable Airship. I have refined metals to great purity and machined them to—great—tolerances; but all this can be duplicated.” The Professor paused and smiled again. “So while I will agree that the construct is not simple, my friend, it is simple enough.”

The helm station was another example of the horribly complex overlaid by barnyard basic. Rotating the spokes did not change the direction of travel, as Carl had assumed from analogy to a steamship; rather, it controlled the amount of power the motor developed. “The diesel runs at constant revolutions,” Erlenwanger said, “with the output delivered through a torque converter.”

“I don’t understand.”

“Oh.” The Professor blinked. “Well, you know how a block and tackle work,” he began. At the end of half an hour’s discussion, Carl
did
understand a torque converter, because he had seen the one in the engine compartment. The diesel squatted there, hot and oily but as silent as heat lightning. The humming of the prop drew up and down the scale as the Professor adjusted its pitch to demonstrate. They went forward again, through the central compartment with its three fold-down bunks and a tiny but marvelously equipped lavatory. Carl was conscious (as he had not been before) of the
machineness
of what they were riding. Flying had been like drifting in a cloud or—better—floating on his back in the stock pond with water-wings at his ankles and neck. Now . . . the diesel made no sound, but the gondola trembled to its power; and the linkage of control to power to motion had become part of Carl’s universe. Amazed by the concept rather than any single object, Carl and Molly watched Erlenwanger change their direction by turning the helm on the axis of its vertical support.

“What do these do?” Carl asked, reaching out a hand toward the levers in front of the helm.

“Oh, careful—” Molly cried, her own hand catching Carl’s. “These spill the gas out through the top. As low as we are now, we could—well, it wouldn’t be a pleasant drop.”