By then, the zeppelin was halfway to the roof. From their position atop the nacelle, they were shielded from eyes below. But the prop wash was picking up, and it was becoming harder to hold on to the slick, rounded surface. Austin looked up and saw a rectangular open- ing where the struts disappeared into the fuselage. He yelled at Zavala, but his words were blown away by the wind, so he simply pointed. Zavala answered, and although Austin couldn't hear his partner's reply, he was sure Joe was saying, "After you."

Austin began to climb. The strut had been made with ladder rungs to allow an engineer access to the engine pod for midair repairs. With the prop turning and the zeppelin rising, the journey of several feet was the ultimate challenge. Austin's progress wasn't pretty, but he made it through the rectangular opening in the zeppelin's belly.

Once out of the main force of the prop wash, he hung on the lad- der and looked back. Zavala was right behind him. The zeppelin had risen through the top of the dome, and the doors in the roof were closing. The people in the dome looked to be the size of ants. By the time Zavala made it into the fuselage, the dome was closed completely. Having made their decision to stow away, he and Zavala had no other choice. They began to climb into the darkness.

THE NIETZSCHE WAS a miracle of aeronautical design. Twice as long as a Booing 747 Jumbo Jet, it had been built in an age before computers and space-age materials. The Nietzsche had been modeled after the Graf Zeppelin, the 776-foot-long silver cigar built in 1928 by airship pioneer Hugo Eckener, but innovations that would later be part of the Hindenburg had also been incorporated into the design. In the Graf, passenger quarters were behind the control room. But the Nietzsche had been designed with living space within the fuselage itself.

Once inside the fuselage, Austin and Zavala found themselves in a small room, after their perilous climb from the nacelle. Hanging on the wall were machinists' tools and spare parts and long black leather coats like those favored by aviators of a bygone era. The room was unheated, and the coats would come in handy for those who worked there. Austin tried a coat on and found that it fit.

"You look like the Red Baron," Zavala said.

Austin slipped a leather cap down on his head. "I prefer to think of myself as a master of disguise." Seeing the skepticism in his part- ner's face, Austin said: "Maybe you've noticed that we're somewhat different in appearance from the Eskimo gentlemen we've seen on this little adventure. If these ridiculous outfits give us a second's edge, they might be worth it."

"The sacrifices I make for NUMA," Zavala said, searching for a coat that fit him.

The room's single door opened onto a long corridor. The walls of the plushly carpeted passageway were decorated with fanciful scenes of men in top hats flying a variety of odd-shaped hot-air balloons and flying machines. Antique crystal lamps hung from the ceiling. At the end of the corridor was a passenger area of comfortably appointed staterooms, each with two berths and its own unique pattern of flow- ery wallpaper.

A short walk led to an elegant dining salon. There were about a dozen small rectangular tables, each covered with a white tablecloth, neatly creased napkins set in place. Two upholstered chairs with ma- hogany arms and legs were pulled slightly back from each table, as if guests were to arrive momentarily.

Tall curtained windows would have given the diners a God's-eye view of the world below. Next to the dining room was a lounge, complete with bar and bandstand, and a dance floor of highly pol- ished wood. Like the dining salon, the lounge was decorated in Art Deco motif. Geometric patterns prevailed. The wall behind the bar was an art gallery ofzeppelin photos.

The lounge was hushed except for the muted rumble of engines.

Zavala looked around in wonder. "This is like being on an old ocean liner."

"Just pray that it isn't the Titanic," Austin said.

Austin led the way toward a room furnished with leather sofas and chairs. His knowledge of German was limited, but he guessed that the sign on the wall designated the area as the smoking room. They left the room and followed another corridor that led to an expansive space that seemed to be a work area. They could see a large functional table illuminated by halogen lamps, computers and several chairs that were designed more for function than comfort. Part of the room was in shadow. Austin found a wall light switch and flicked it on. The entire room was flooded with light, and both men tensed when they discovered that they were not alone. Two figures stood against the far wall, and Zavala swore in Spanish. Out of the corner of his eye, Austin saw the shotgun coming to bear.

"Wait!" he said.

Zavala lowered the gun and smiled as he studied the figures. He was looking at the mummified bodies of two men, propped up on metal stands. They stood in a natural position, arms hanging down by their sides. Their skin was as dark as leather and stretched tightly against their skulls. The eye sockets were empty, but the faces were remarkably well preserved. Austin and Zavala moved in for a closer look.

Zavala said, "I don't think these guys are the Blues Brothers."

"I don't think they're brothers at all. Judging from their clothing, I'd say they come from different eras."

One man was dressed in a heavy shirt and leggings of coarse ma- terial. His dark hair hung down to his shoulders. The taller man had short blond hair and wore a pro-World War II leather coat, not unlike the ones Austin and Zavala were wearing. Hanging above the mummies was a large, ragged-edged piece of aluminum. The word Nietzsche was printed on it.

Next to the mummies was a glass display case like those found in museums. Inside the case were a Leica 35mm still camera and sev- eral lenses, a Zeiss movie camera, charts of the northern hemisphere and a leather-bound book. Austin opened the case and leafed through the pages of the book. It was filled with entries in German, stopping in 1935. He stuffed the book into his pocket. He was examining a dis- play of Eskimo harpoons and knives, when Zavala called him over.

"Kurt. You've got to see this."

Zavala had wandered over to the long ebony chest that rested on a waist-high platform. On top of the chest was a horn that looked as if it had been made from an elephant's tusk. The instrument was studded with gems and banded in gold. Austin carefully removed the horn and handed it to Zavala, who marveled at the detail of the bat- tle scenes carved into the ivory.

Austin opened the chest and pushed back the lid. Lying on pur- ple velvet inside the chest was a sword in its scabbard. He lifted the leather scabbard from the chest and inspected the gold-clad hilt and hand guard. Set into the heavy triangular pommel was a huge ruby. The elaborate hand guard was etched with flowers. He mused at the incongruity of the beautiful decoration on a weapon with such deadly potential.

He hefted the two-edged sword, feeling the perfect balance, then gingerly drew the weapon from the scabbard. An electric thrill seemed to run through his arm. Could this be Durendal, the fabled weapon that Roland swung against the Saracens? The blade was chipped here and there. A picture flitted through his mind of Roland banging the sword against a stone so that it wouldn't fall into the hands of the enemy.

Zavala whistled. "That thing must be worth a fortune." Austin thought about all the time and money Balthazar Aguirrez had expended in his search for the object in his hand. "It's worth a lot more than that," he said.