CHAPTER XIV

BUILDING AN AIR SHIP

When Ned announced to Alan that they would at once unpack and test the motor—"for we might as well stop if the engine isn't right," as he put it—all thoughts of the troubles of the early day vanished. And the motor certainly was a beauty. Though some expert had recommended the French motor, Ned had preferred to use one made in America, not only because he had been able to get it quicker but because he believed it as good as the foreign make.

The engine had eight air-cooled cylinders, in two sets of four, placed at an angle of ninety degrees to each other. The crank case was of aluminum and the shaft of vanadium steel, hollow, and specially treated to insure toughness. All the studs or bolts were of the same steel. Complete, with balance wheel, it weighed two hundred pounds. The ignition was accomplished by six dry batteries and a single-wire vibrating coil. It was rated at fifty horsepower.

So exactly had the preliminary work been done at the factory that in two hours the boys were able to have the engine bolted to the section of the car where it was to be used, and before evening the radiator tubes and pump of the cooling system were also in place. Temporary connections were set up and the sparking wires attached, and then the reservoir was filled with gasoline. A little jar as the wheel was turned, then a couple of sharp explosions, and the engine fell to its work as if it had been running for weeks.

Ned shut it off after a moment's critical inspection.

"Let her flicker!" pleaded Alan. "We've waited so long for a real one that I like to hear her buzz."

"We'll let her buzz when we can use the buzz," laughed Ned. "Gasoline is gasoline, you know."

Night did not stop the work of the eager lads. As soon as they had eaten a light meal, Ned and Alan, with a couple of lanterns and a half dozen of candles, began to adjust the sections of the car. These, seven in number, when joined, were 54.12 feet in length. The American spruce frame and the aluminum joints were all intact. This work finished the day.

Blankets on the rough floor were good enough for the explorers that night. The luxury of the Placida's mattresses and fresh sheets was missed, as was Elmer's skill as a chef when it was time for breakfast the next morning. The boys were not so indifferent about this meal as they had been about that of the evening before. They had no stove, but they took the time to arrange a regular camp in a comer of the corral. A little fire was soon burning, at which they made coffee and toasted some bacon. This, with hardtack and some preserved fruit, they thought was enough, for they were determined not to disturb the carefully packed provisions that were to be carried in the balloon.

"Have you had enough?" asked Ned as the last piece of scorched bacon disappeared.

"Enough?" answered Alan. "A regular banquet!"

Just then there was a loud thump on the closed door of the barn.

"The hands are arriving," explained Ned, and he hastened to open the door.

A few of the workmen were there, but the knocking had been done by a pleasant faced woman—apparently a Mexican. A black shawl covered her head and one arm. It was Mrs. Bourke, Buck's wife.

"I thought," she said smiling, "hungry."

Without further words she threw back the shawl and revealed a small tin pail. The appetizing odor made Ned's mouth water. In the bottom of the bucket were frijoles, or boiled and fried Mexican black beans cooked in pepper, and on top of these were a half dozen smoking hot tortillas or corn cakes.

"Mrs. Buck," exclaimed Alan, "you have saved our lives!"

All recollection of his recent banquet seemed to have disappeared, and so did Mrs. Bourke's bucket of beans and cakes, in double-quick order. The reward was a bright silver dollar for the thoughtful woman and a contract that she should come three times a day and prepare the boys' meals. It would have been easier to have gone to Buck's home, only a short distance away, but the boys were now determined to stay in the corral, or leave it only one at a time. However, they soon developed a taste for Mrs. Bourke's peculiar hot wholesome dishes and these, with what provisions they had on hand, were a fair substitute for Elmer's cooking.

The frijoles having been disposed of, Ned at once went out, and was fortunate in finding a load of rough lumber and a sort of jack-carpenter. With the help of the boys a four foot-high series of "horses" or frames was set up in the center of the corral. This was for the car to rest on while it was being assembled. It was elevated so that the propeller and aeroplanes and rudder could all be tested after being set up. The propeller, 11.48 feet in length, revolved in bearings four feet above the bottom of the car.

After noonday refreshment the middle section of the car, to which the engine was already attached, was carefully lifted into place with the aid of the workmen, and then the laborers were paid off and dismissed—all except the watchmen. From now on there was nothing that the boys could not do themselves, and they wanted to be undisturbed and alone. The putting together of the car was a treat of which they had long dreamed and they were happy in their work.

The remaining sections were easily laid on 'the "horses" and then came the bolts and the bracing with piano wire. When brought together the fifty-four foot long skeleton was in shape much like a cigar. The main frame was six feet high, tapering to five feet at each end. In depth the dimensions were the same. The engine rested on the floor of the middle section and was accessible in all its parts from that compartment. An elevation of the floor in the forward part of this section made it possible for one to stand high enough to have an outlook in all directions through openings in a hooded elevation that projected above the top of the section.

This hood was of a waterproof silk, coated with powdered aluminum, that metal being used because of its semi-incombustibility. This silk also covered the sides of the central compartment, making a wind-, rain- and waterproof cabin. The lookout windows on all four sides were covered with isinglass. The bottom of the framework of the car forward and aft of the engine compartment had a ladder-like flooring of spruce, inserted more for strengthening the car than for service. But on top of the car, reaching from end to end, was a continuous runway two feet wide which could be used in hurriedly visiting either propeller or rudder. This runway was protected by guide ropes of Italian hemp running through posts extended upward from the sides of the car. The top of the engine compartment was completely floored, making a platform 6 x 6.12 feet square. This was surrounded by a protecting network, and Alan named it the "bridge."

A light rope-ladder extended into the engine cabin from an opening in the roof, making the top floor space or bridge and the upper runways quickly accessible. The gasoline reservoir, just forward of the engine, was connected with the bridge by a copper supply pipe. The extra supply of gasoline was to be carried on the bridge in the open air, and lashed to the netting instead of being stored in permanent reservoirs as is the usual practice. This was in order that the empty vessels might be thrown overboard when it was necessary to lighten the balloon.

The other sections of the car were each 8 feet long and decreasing in height from 6 feet next the cabin to 5 feet at the end of the car. In the two sections just forward of the cabin and in the two just aft provision had been made for attaching the eight liquid hydrogen casks—four at each end. As this liquid was reconverted into gas the light sheet-iron casings might likewise be cast overboard to lighten the balloon. As needed, the liquid hydrogen jars, coated with mercury, were to be taken from their casings and carried to the bridge where the reconverter was located.

Aft of the engine cabin was the store room for water and provisions. The grooves and rods for the counterweights and equilibrium adjuster ran in the middle of the upper footway and the propeller shaft rested on the bottom of the forward section of the car.

At ten o'clock that evening all the work on the car was finished except the buckling on of the aluminum silk sides and the hanging of the propeller, the rudder and the aeroplane sides. It was as long and as hard a day's work as either of the boys had ever done. They were dead tired, but happy, and after a sousing wash-up they got into their pajamas and, throwing their blankets on the floor of the little office, were soon fast asleep.