"As far as we can reach, at least. It's put on to keep gunk from the engine from damaging the fabric." Illya looked around, trying to locate an available entrance. Something caught his eye. "Maybe we're in luck after all," he said and started moving along the horizontal struts to a different area, keeping a careful watch to the front as he went. Finally he crouched low and eased the last few feet to the dirigible body. Holding to a strut over his head with one hand, he took the knife with the other and carefully placed it, point first, against a point on the metal covered fabric. "Pity Ishmael didn't supply us with screwdrivers, along with the other stuff," he said.

After a moment's effort, the knife turned. Illya carefully unscrewed something, moved the knife to a second spot and repeated the performance.

Napoleon watched for some time, then edged out on the struts. "If you're planning to unscrew the engine, let me know and I'll get off."

Illya carefully fitted the knife into another screw head. "As long as you're here, make yourself useful. Reach over my shoulder and hold this thing in place while I get the last screw out."

Napoleon obediently stretched his arm out and placed his hand where Illya indicated. Another half dozen turns of the knife, and he found himself precariously balancing a round metal plate about two feet in diameter. "What is it?" he asked as Illya put the knife away and grasped the plat.

"An inspection hatch," Illya told him. "There are probably a dozen of them around, but this one will be sufficient." He leaned down, dangled the plate for a second, then dropped it with a small thud onto the grass below. "Now let's get inside; they're getting ready to cast off.

The two agents eased through and found themselves in total darkness. "We must be near the keel," Illya whispered. "We'd better get a grip on the girders and work out way up before some wandering Thrush spots us."

"I have a grip and I intend to keep it for awhile," Napoleon said. "Isn't there something we can do right here?"

"Not much. Don't forget that helium is lighter than air so it won't leak out through a hole in the bottom. We have to make out hole in the top of the bags if we want to sink this ship of the air." Illya paused for a moment before continuing. "Some old Russian dirigible lore is coming back to me." Perhaps we won't have to cut any holes."

"Don't tell me there are inspection hatches on the gas bags?"

"Something even handier, if we can find it: valves. They were used to adjust the buoyancy. These engines burned a lot of fuel and on long trips the loss of weight sometimes had to be compensated for."

"Isn't that a rather expensive way? Helium isn't the cheapest gas in the world."

"Necessity knows no expense—old Russian proverb. Besides, this is an old German airship, designed for use with hydrogen. Too bad they aren't still using hydrogen in her; one well placed tracer bullet and the whole thing would go up in flames."

"Your fast store of knowledge is amazing," Napoleon said. "However, I seem to have detected a concealed assumption in your reasoning; we can use the valves if we can find them."

"You missed an earlier assumption," Illya replied. "We can probably find the valves if we can get to the top of gas bags. Shall we start moving?"

Chapter 13

"There Must Be an Operator's Manual In Here Somewhere"

Napoleon hesitantly released one of the girders and reached upward. After a second, he located another handhold and decided he could risk moving one of his feet. As he cautiously lifted his foot and felt about for something solid to put it on, Illya voice came from several feet above him.

"Come on up. There's a catwalk up here, and I think there's some light about a hundred feet toward the front."

Napoleon said nothing, only concentrated on climbing. After a minute, he was standing relatively upright on what felt like a metal strip about a foot wide. Looking toward the forward end of the dirigible, he could make out a faint blob of light. A few feet n front of him, something—presumably Illya—was fuzzily outlined against it.

"I'm here," Napoleon announced. "Keep in mind that despite what we're standing on, I'm not a cat."

"Just follow me. There are plenty of handholds on both sides. The netting around the gas bags is probably the safest thing to grab for in moments of panic, however. Less likely to damage yourself on that than on the outer frame. And remember, if you miss the frame, you can fall right through the fabric covering."

"I'm touched by your concern. Where are we going?"

"Up to the nose and back down through the center if we're lucky," Illya said.

"Down the center? The keel, you mean? We just left that."

"No, the center. The gas bags are probably doughnut shaped and if they are, there will be a catwalk right through the center, from nose to tail. Somewhere along it, there should be a ladder going up. And there should be at least one other catwalk along the top of the gas bags."

"You make this thing sound like a floating briar patch."

"Most dirigibles were. Let's just hope Brer Thrush doesn't spot us and follow us in."

The blob of light was bigger now, and they could see a second one further down where the shell started curving in toward the nose. Soon they reached the first area of light. It was coming faintly from the open space between tow gas bags.

The two agents halted, and Illya peered cautiously around the main-frame girders that marked the division between the bags. After a second, he moved quickly across and motioned Napoleon to do the same.

Napoleon glanced around the edge of the bag and quickly joined Illya in the shadow of the next one. "It looks like a bicycle wheel for the Jolly Green Giant," he remarked as they moved on.

"It works on somewhat the same principle," Illya replied. "Those wires do most of the work in holding the ship rigid."

A swaying motion cut off any further information. "Going up," Illya announced. He stopped, took the knife from his pants pocket, braced himself against the lighter girders of one of the intermediate frames, and sawed a slit in the outer fabric. Returning the knife to his pocket, he widened the slit with his fingers and peered out."They have most of the mooring lines loose," he said. "We'll be on our way any minute."

Napoleon gave Illya a hand in getting back onto the catwalk. "Can we find those valves soon enough?" he asked. "El Presidente's palace in Cerro Bueno isn't too far from here, as the dirigible flies."

"If we don't find them, we can start cutting holes in the bags."

The agents started along the catwalk again. They passed another main frame, this one unlighted, and then came to the second blob of light. As before, Illya peer cautiously around the corner before crossing the lighted area. As then moved ahead again, he whispered over his shoulder, "That's probably the light above the control gondola. Any ladders from the center to the upper catwalk will probably be there."

Napoleon remained silent. As they continued moving forward, the curve became more pronounced and soon they were surrounded by darkness. The agents slowed their pace and Illya made sure of his footing before each step.

"At this rate," Napoleon said, "our friends will be over Cerro Bueno before we find the nose of the dirigible."