The present story commences soon after the return of the party from the Far West, when they were much surprised—­as has been said—­to observe the mushroom-like rise of the Mortlake factory.  But of what the new plant was to mean to them, and how intimately they were to be brought in contact with it, none of them guessed.

“Well, Mortlake,” observed Mr. Harding, in his harsh, squeaky voice—­not unlike the complaint of a long unused door, “well, Mortlake, we are getting ahead, I see.”

The two men had, by this time, passed within the big sliding doors of the freshly-painted shed, and now stood in a maze of machinery and strange looking bits of apparatus.  From skylights in the roof—­there were no side windows to gratify the inquisitive—­the sunlight streamed down on three or four partially completed aircraft.  With their yellow wings of vulcanized cloth, and their slender bodies, like long tails, they resembled so many dragon-flies, or “devil’s darning needles,” assembled in conclave upon the level floor.  At the farther end of the shed was a small blast furnace, shooting upward a livid, blue spout of flame, which roared savagely.  Actively engaged at their various tasks at lathes and work-benches, were a dozen or more overalled mechanics, the most skillful in their line that could be gathered.  Here and there were the motors, the driving power of the “dragon flies.”  The engines glistened with new paint and bright brass and copper parts.  Behind them were ranged big propellers of laminated, or joined wood, in stripes of brown and yellow timber.  Altogether, the Mortlake plant was as complete a one for the manufacture of aerial machines as could have been found in the country.

“Yes, we are getting along, Mr. Harding,” returned Mortlake, “and it’s time, too.  By the way, Lieut.  Bradbury is due here at noon.  I want to have everything as far advanced as possible in time for his visit.  You won’t mind accompanying me then, while I oversee the workmen?”

Followed by Mr. Harding, he made an active, nervous tour of the work-benches, dropping a reproof here and a nod of commendation or advice there.

When he saw a chance, Mr. Harding spoke.

“So the government really means to give us an opportunity to show the worth of our machines?” he grated out, rubbing his hands as if washing them in some sort of invisible soap.

“Yes, so it seems.  At any rate, they notified me that this officer would be here to-day to inspect the place.  It means a great deal for us if the government consents to adopt our form of machine for the naval experiments.”

“To us!  To you, you mean,” echoed Mr. Harding, with an unpleasant laugh.  “I’ve put enough capital into this thing now, Mortlake.  I’m not the man to throw good money after bad.  If we are defeated by any other make of machine at the tests I mean to sell the whole thing and at least realize what I’ve put into it.”

Mortlake turned a little pale under his swarthy skin.  He rubbed his blue chin nervously.