“Of course. It is the application of the second law of thermodynamics.”
“It is indeed. The ideal cycle of four reversible changes in the physical condition of a substance. A steam engine works in a Carnot cycle, though since the source of energy is external it is not a perfect cycle. In my Carnot engine I am attempting to combine the complete cycle in a single unit. I first used coal dust as a fuel, fed into the cylinder fast enough so that isothermal
expansion would take place when it burned.”
“And the results?” Parrott asked enthusiastically.
“Alas, dubious at best. It was hard to keep the cylinder temperature high enough to assure combustion. Then there is the nature of the fuel itself. Unless it is ground exceedingly fine, a weary and expensive process at best, it tended to lump and clog the feed tube. To get around that problem I am now working with coal oil and other combustible liquids with improved results.”
“How wonderful! You will have a self-contained engine under each turret then. You will keep me informed of your progress?”
“Of course.”
Parrott thought of the patent of the land battery that had been hanging on his office wall for many years. A most practical idea. Lacking only an engine sufficiently small to move it.
Was Ericsson’s machine going to fulfill that role?
Gustavus Fox was signing papers at his desk when the two Irish officers came in. He waved them to the waiting chairs, then finished his task and put his pen aside.
“General Meagher — do I have your permission to ask Lieutenant Riley a few questions?”
“Ask away, your honor.”
“Thank you. Lieutenant, I noticed that scar on your right cheek.”
“Sir?” Riley looked concerned, started to touch the scar, then dropped his hand.
“Could that scar once have been — the letter ‘D’?”
Riley’s fair skin turned bright red and he stammered an answer. “It was, sir, but…”
“You were a San Patricio?”
Riley nodded slowly, slumped miserably in his chair.
“Mr. Fox,” Meagher said. “Could you tell me just what this is all about?”
“I will. It happened some years ago when this country went to war against Mexico. Forty years ago. There were Irish soldiers in the American army even then. Good, loyal soldiers. Except for those who deserted and joined the Mexican army to fight for the Mexican cause.”
“You never!” Meagher cried out, fists clenched as he rose to his feet.
“I didn’t, General, please. Let me explain…”
“You will — and fast, boyo!”
“It was the Company of Saint Patrick, the San Patricios they called us in Spanish. Most of the company were deserters from the American army. But I wasn’t, sir! I had just come from Ireland and I was in Texas on a mule train. I was never in the American army. I joined the Mexicans for the money and everything. Then when we were captured General Winfield Scott wanted to hang the lot of us. Some were hung, others got off with being lashed and branded with the ‘D’ for deserter. I swore I had never been in the army, and they could find no record of me whatsoever. They believed me then so I didn’t get the fifty lashes. But they said I still fought against this country so I was branded and let go. I rubbed the brand, broke the scab and all, so you couldn’t see the letter.” Riley raised his head and straightened in his chair.
“That’s the whole of it, General Meagher. I swear on the Holy Bible. I was a lad from Kerry, some months off the boat, and I made a mistake. Not a day has gone by that I didn’t regret what I had done. I joined this army and I have fought for this country. And that is all I ever want to do.”
Meagher wrinkled his brow in thought; Fox spoke.
“What do you think, General? Do you believe him? I will leave the decision to you.”
Meagher nodded. Lieutenant Riley sat erect, his skin pale as death. Seconds passed before Meagher spoke.
“I believe him, Mr. Fox. He is a good soldier with a good record and I think he has more than paid for what he did so long ago. I’ll have him — if you agree.”
“Of course. I think the lieutenant will be a better soldier now that the past is known. Perhaps he can finally put the past behind him.”