“One week,” Douglass said ominously. Then a sudden smile flickered briefly across his severe features. “I like your style, Mr. Ericsson. You are a man of uncommon good sense.”
“I am a man who builds ships, Mr. Douglass. I have never understood the American preoccupation with the color of a man’s skin. If a workman does his job I don’t care if he is even a…” He groped for an apt comparison. “Even a Norwegian — and I will still employ him.”
The wail of a steam whistle interrupted him. “Ahh, you must excuse me,” he said. Turning and leaving abruptly, heading towards the puffing sound of a locomotive. He had insisted that a spur track of the Chesapeake Ohio railroad be built, coming right into the shipyard. It was already proving its worth, bringing iron plating right to the dockside.
But this was no ordinary cargo of iron. The train consisted of a single passenger coach behind the engine, with a heavily laden flatcar behind that. A stubby man in a frockcoat, wearing a black stovepipe hat, climbed down from the coach as Ericsson came up.
“Could you possibly be Mr. Ericsson?” he said, extending his hand. “My name is Parrott, William Parker Parrott.”
“The gunsmith! This is a great pleasure. I have designed guns myself so know of what I speak. And this is the 12-inch cannon that you wrote me about.”
“It is.”
“Beautiful,” Ericsson said as they both stepped back to admire the bulk of the long, black gun. Beauty is in the eye of the beholder for this was a hulking black engine of destruction. “Your locking breech, this I must see at once.”
They both clambered up onto the flatcar, in their enthusiasm not noticing the soot that smeared onto them.
“The gas seal,” Parrott said, “that is the heart of a breechloading gun. I have examined closely the British Armstrong cannon, have even built one of them. Its breech is complex and when firing begins it soon becomes unusable. A sliding metal plate is secured in place by large locking screws. But the seal is incomplete. After a few rounds the heated metal expands and leaks hot gas and threatens the very safety of the crew should the breech explode — as has happened more than once. But I believe that I have now solved that problem.”
“You must tell me — show me!”
“I shall. The principle is a simple one. Imagine, if you will, a heavy threaded breach, into which a threaded bolt can be screwed into place.”
“The gas seal would be complete. But it would be the devil’s own job — and a slow one at that — to screw a long bolt in and out between each shot.”
“Of course. So let me show you…”
Parrott went to the rear of the gun and reached up to strain at a long lever. He could barely reach it, nor was he able to pull it down. The taller Swede who, despite his advanced age, was immensely strong, reached past the small gunsmith and pulled the bar down with a mighty heave. The breech-block rotated — then swung aside on a large pinned hinge. Ericsson ran his fingers over the threads on block and barrel.
“It is an interrupted screw,” Parrott said proudly. “The theory is a simple one — but getting the machining right was very difficult. As you can see, after the breach and the breechblock have been threaded, channels are cut in each of them. The block then slides forward into place. And with a twist it locks. A perfect gas seal has been accomplished by the threading. After firing the process is reversed.”
“You are indeed a genius,” Ericsson said, running his fingers over the thick iron screw threads. Possibly the only time in his life that he had praised another man.
“If you will show me the ship on which it will be mounted…”
“Difficult to do,” Ericsson said, smiling as he tapped his head. “Most of it is inside here. But I can show you the drawings I have made. If you will step inside my office.”
Ericsson had not stinted himself with the government’s money when he had designed a workplace for himself. He had labored for too many years in the past in drafty drawing rooms, sometimes only feebly lit by sooty lanterns. Now large windows — as well as a skylight — illuminated his handsome mahogany-framed drafting table. Shelves beside it contained models of the various ships he had designed, other inventions as well. The drawing of Virginia was spread across the table. He tapped it proudly with his finger.
“There will be a turret here on the forelock, another aft. Each will mount two of your guns.”
Parrott listened intently as the Swedish engineer proudly pointed out the details that would be incorporated into his latest design. But his eyes kept wandering to a chunky metal device that stood on the floor. It had pipes sticking out from it and what appeared to be a rotating shaft projecting from one side. At last he could control his curiosity no longer. He tried to interrupt, but Ericsson was in full spate.
“These turrets will be far smaller than those I have built before because there will be no need to pull the gun back into the turret after firing to reload through the muzzle. Being smaller the turret will be lighter, and that much easier to rotate. And without the need of pulling the guns in and out after each shot the rate of fire will be faster.”
He laughed as he clapped the small man on the back, sent him staggering. “There will be two turrets, four guns. And I shall design the fastest armored ship in the world to carry these guns into battle. No ship now afloat will stand against her!”
He stepped back, smiling down at his design, and Parrott finally had a chance to speak. “Excellent, excellent indeed. When I return I shall begin work on the other three guns at once. But pardon me, if you don’t mind — could you tell me what this machine is?”
He tapped the black metal surface of the machine and Ericsson turned his way.
“That is a prototype, still under development.” He pointed back at the drawings of his iron ship. “This new ship will be big — and with size comes problems. Here look at this.”
He picked up a half-model of Monitor and pointed out the steam boiler. “A single source of steam here, that is more than enough in a ship this size. The turret you will notice is almost directly above the boiler. So it was simple enough to run a steam line to it to power the small steam engine that rotates the turret. But here, look at the drawing of Virginia. Her engine is on the lowest deck. While the turrets are far above, fore and aft. This means that I will need insulated steam lines going right through the ship. Even when they are insulated they get very hot. And there is the danger of ruptures, natural or caused by enemy fire. Live steam is not a nice thing to be near. Should I have a separate boiler under each turret? Not very practical. I have considered this matter deeply, and in the end I have decided to do it this way.”
“You have considered electric motors?”
“I have. But none are large enough to move my turrets. And the generators are large, clumsy and inefficient. So I am considering a mechanical answer.” He looked over at the engineer. “You have heard of the Carnot cycle?”