He had figured out how that little copper tube would make Bell’s flying machine smash. It was as ingenious as it was horrific. The Eagle’s Gnome rotary engine was fuel lubricated. It had no oil reservoir, no crankcase, no pump to maintain oil pressure—in fact, no oil at all. The castor oil suspended in the gasoline did the job of oil, greasing the passage of the piston through each of the cylinders. It mixed in readily because castor oil dissolved in gasoline.

Like paraffin. The paraffin wax that plugged the copper tube would also dissolve in gasoline. When the gas melted the plugs, in an hour or so, the water would leak out and contaminate the fuel. Two tablespoons of water in a flying-machine gas tank was more than enough to stop Isaac Bell’s engine dead. Were he flying high at the time, he might manage to volplane down safely. But if he was taking off, or attempting to alight, or making a tight turn low to the ground, he would smash.

ISAAC BELL LISTENED WITH DEEP CONCERN, but not much surprise, as Eddie Edwards reported grim news he had just learned from a contact in the United States Army. Someone had executed a daring raid on the arsenal at Fort Riley, Kansas.

“The Army’s hushed it up,” Eddie explained, “criminals busting into their arsenal not being the sort of event they want to read in the newspaper.”

“What did they get?”

“Two air-cooled, belt-fed Colt-Browning M1895 machine guns.”

“Had to be Frost,” said Bell, picturing in his mind the four-hundred-and-fifty-rounds-per-minute weapons enveloping Josephine’s monoplane in blizzards of flying lead.

“You gotta hand it to him, that man’s got nerve. Right under the nose of the U.S. Army.”

“How’d he break in?” Bell asked.

“The usual way. Bribed a quartermaster.”

“I find it hard to imagine that even a quartermaster more larcenous than most his ilk would risk the Army not noticing missing machine guns.”

“Frost tricked him into thinking he was stealing surplus uniforms. Said he was selling them in Mexico, or some cock-and-bull story the quartermaster believed. Or wanted to believe. A drinking man, needless to say. Anyhow, he got the surprise of his life when he woke up in the stockade. But by then the guns were long gone.”

“When did this happen?”

“Three days ago.”

Bell pulled the topographic map of Kansas down from the hangar-car ceiling. “Plenty of time for Frost to get between us and Wichita.”

“That’s why I said we have trouble. Though I do wonder how he’ll fit two machine guns in a Thomas Flyer. Much less hide them. Takes three men to mount one of those guns. They weigh nearly four hundred pounds with their landing carriage.”

“He’s strong enough to pick one up himself. Besides, he has two helpers in that Thomas.”