This last was a marvel of skill, for it contained besides the gas machine, and the motor for working the propellers, dynamos, gages, and instruments for telling the speed and height, motors for doing various pieces of work, levers, wheels, cogs, gears, tanks for storing the lifting gas, and other features of interest.

There were several staterooms for the use of the young captain and the passengers, an observation and steering tower, a living-room, where they could all assemble as the ship was sailing through the air, and a completely equipped kitchen.

This last was Mr. Damon’s special pride, as he was a sort of cook, and he liked nothing better than to get up a meal when the craft was two or three miles high, and scudding along at seventy-five miles an hour.

In addition there were to be taken along many scientific instruments, weapons of defense and offense, in addition to the electric rifle, and various other objects which will be spoken of in due time.

“Well,” remarked Tom Swift one afternoon, following a hard day’s work in the shop, “I think, if all goes well, and we have good weather, I’ll give the Black Hawk a trial tomorrow.”

“Do you think it will fly?” asked Ned.

“There is no telling,” was the answer of the young inventor.  “These things are more or less guesswork, even when you make two exactly alike.  As far as I can tell, we have now a better craft than the Red Cloud was, but it remains to be seen how she will behave.”

They worked late that night, putting the finishing touches on the Black Hawk, and in the morning the new airship was wheeled out of the shed, and placed on the level starting ground, ready for the trial flight.

Only the bare machinery was in her, as yet, and the gas bag had not been inflated as Tom wanted to try the plane feature first.  But the vapor machine was all ready to start generating the gas whenever it was needed.  Nor was the Black Hawk painted and decorated as she would be when ready to be sent to Africa.  On the whole, she looked rather crude as she rested there on the bicycle wheels, awaiting the starting of the big propellers.  As the stores and supplies were not yet in, Tom took aboard, in addition to Mr. Damon, Ned, his father, Mr. Jackson and Mr. Durban, some bags of sand to represent the extra weight that would have to be carried.

“If she’ll rise with this load she’ll do,” announced the young inventor, as he went carefully over the craft, looking to see that everything was in shape.

“If she does rise it will be a new experience for me,” spoke the old elephant hunter.  “I’ve never been in an airship before.  It doesn’t seem possible that we can get up in the air with this machine.”

“Maybe we won’t,” spoke Tom, who was always a little diffident about a new piece of machinery.

“Well, if it doesn’t do it the first time, it will the second, or the fifty-second,” declared Ned Newton.  “Tom Swift doesn’t give up until he succeeds.”