by Eric Flint
So letters to General Shein were still letters, and radio messages to Ufa had to be transcribed by someone and sent part of the way by boat. Still, the ladies learned of the loss of the Czarina Evdokia almost before anyone else in Russia. It was discussed and considered in the monastery, and the conclusion was that if it had happened in July or even August or September, it might have been a fatal blow to the czar’s prestige. But now—especially since it happened in far off Germany—it was less important. It would damage Czar Mikhail’s position, but not fatally.
Hamburg
February 1637
The room was small, but surprisingly modern and cozy warm. It had steam heat. The designers had integrated the condensers with the heating system. That was going to be important where they were going, and it was nice even here in Hamburg. The walls were six-inch-thick panels filled with foamed rosin. The windows were double-paned which, combined with the less-than-perfect flatness, meant that they were fine for letting light in, but mostly useless for looking out of. Mikey was holding his stuffed Brillo. Brandy smiled, thinking of the book of stories about the fictional ram, Brillo, and his constant hunt for freedom. She even knew the real Brillo and his owner Flo. But little Mikey loved the stories and loved his stuffed toy.
His crib was locked into the corner and their bed was in the other corner. Brandy could see right now that there wasn’t going to be a lot of privacy. It was a ten-by-twelve-foot room with a low ceiling, and the bed folded up into a couch. There was a table that at the moment was folded up next to the wall. The ceiling was low enough that Brandy was afraid that she would bump her head, and Valeriya Zakharovna was in real danger of it.
Mikey dropped Brillo and wobbled over to the tie downs for the table. Brandy rushed over to keep him from hurting himself in his explorations. As she was scooping him up, Vlad came in, wearing a fur coat.
“Brrr,” he stuttered. “Say, it’s warm in here.”
“Steam heat.” Brandy pointed. Vlad went over and put his hands out. “Careful. It’ll burn your hands if you touch it.”
“They aren’t running the engines, are they?”
“Charging the batteries, maybe?”
“Maybe,” Vlad agreed.
“In the meantime, I want some sort of a screen over the radiator there. The burned hand may teach best, but I don’t want Mikey learning that way.”
Vladimir nodded. “I’ll talk to John about it. Meanwhile, let’s you, me, and Mikey adjourn to the wardroom.”
In the wardroom, Captain John Adams and Petr Nickovich were arguing about the winches for the sails. The Catherine the Great was intended to spend most of her time as a sailing ship, with her treads raised up out of the water. That had proven to be one of the most difficult aspects of the whole tread concept, and one of the less necessary ones, in Vladimir’s opinion. A combination sail and paddle wheel ship would leave the wheels in the water while it was under sail and they had apparently worked well enough. But John had insisted that the whole tread assembly had to be adjustable. He did have a point. The paddle wheel sailing ships had not been icebreakers. A North Sea ice floe would turn a paddle wheel into so much scrap lumber in a trice. The treads were designed to take rough handling and the paddles on them were removable.
“It’s going to freeze!” John Adams roared and Vladimir’s wandering thoughts were dragged back to the discussion. Vladimir had seen portraits of the founding father, and based on that he suspected that Captain John Adams of Portsmouth, England was related in some way to President John Adams, USA. A great granduncle several times removed or the like. Because Captain Adams looked rather like the president. At forty he was a short, florid-faced man with graying hair and a hairline that wasn’t just retreating but in full rout. And he had a voice that cut through the surrounding noise like a cleaver.
“What’s going to freeze?” Brandy asked. “And please, John, we are not in the midst of a sea battle. You don’t need to make yourself heard over the roar of cannon.”
“Cannon.” John paused and visibly took a deep breath.
Petr Nickovich started to interrupt but Vladimir gave him a cautioning look and the Russian scientist subsided. That was precisely what Petr Nickovich was, a true scientist. You might need both hands to count the number of people on Earth who knew more of airships and the principles they worked on than Petr Nickovich, but Vladimir doubted it.
“The electric motor! He wants to use it for the mainsail winch,” John explained in a voice that carried fewer decibels but no less intensity.
“It can be insulated and the chain drive that Captain Adams wants to use instead will freeze even more readily. It will also represent a danger for everyone on deck.”
Ah. It was the chain versus electricity argument that Petr and John had been having almost since Petr had arrived. John wanted to use direct, or at least reasonably direct, mechanical linkages for everything. Or at least as much of everything as he could manage. Petr noted that the steam engines were going to run generators anyway to power lights and radio. He wanted to make the generators bigger and basically run everything off electrical power. They both had fairly good points, but in Vladimir’s opinion John had the better one. You lost energy in converting mechanical power into electrical, then again in converting it back. There was a reason that the Catharine the Great had sails. The less of its cargo space that was loaded with fuel, the more could be filled with goods. Spending extra fuel to convert the mechanical energy of the steam engines into electricity and then back into mechanical energy was just wasteful.
Petr had given up on using electric motors to power the treads only after the chain gears had actually been installed.
“Captain, what about the risk from the chains?” Brandy asked calmly.
“There is some, but it shouldn’t be too bad. We can put a railing around the chains.”
“And the freezing?”
“The chains are a robust system. They will freeze, but the engine will break the ice.”
“So would—” Petr started, but Vladimir held up a hand and he quieted, sullenly.
“Surely we could install a powerful electric motor at the winch location and that would eliminate the need for the long chain drive along the deck,” Brandy said.
The main steam engine was located aft, and the sail in question was the foresail. A chain drive from the engines to a winch at the foresail would travel close to fifty feet. That would be a heck of a long chain and plenty of opportunity for accidents and failure.
“How much energy are you going to lose in chain friction over that distance?” Vladimir asked.
“Some,” Captain Adams conceded grudgingly. “But the chain drive is a system all my people are familiar with by now. We know how to fix them when they break. Electric motors are fragile things, and expensive. Only Karl Weber is really comfortable around electrical systems at all, and he’s the radio man.”
“Electric motors are basically simple devices,” Petr Nickovich said. “I know how to deal with them and I can train the crew.”
It took another hour of discussion, but Petr Nickovich got his electric winch for the foresail.
The Catherine was almost completed, and they were still doing design modifications. That was because a ship was not a log, or even just a floating hull. It was a complex of systems that had to interact with each other, and all of which had to be hardened against stresses that no land-based building would have to deal with except in the middle of an earthquake.
“What’s the situation in regard to the cargo?” John asked, after he grudgingly conceded that in this case an electric winch might be the better choice.
“We’re ready when you are, John. It’s all in a warehouse right here in Hamburg. Including two hundred pounds of powdered red and yellow dye from the fabworks.” Considering that a one ounce packet of the dye was enough to color four shirts or fifty sheets of paper, a hundred pounds was a lot. There was also a set of plates for the printing of money, two hundred of the new radio tubes, lathe heads
, instruction books, and wagon-portable metal detectors, as well as a host of other stuff.
“Prince Vladimir, let me again ask that I be allowed to take the Catherine on a shakedown cruise out to the North Sea ice packs to see how it operates. Before we attempt the North Sea route.”
Vladimir shook his head. “You’re right, Captain, and I know you’re right. But it would be at least another month to make that cruise and we need to get to Russia soon. In fact, we should already have been there.”
Pechora Sea
“Ice ho!” the lookout called.
Vladimir headed for the bridge. It had clear glass windows, the still very expensive sort. The Catherine the Great was under full sail and approaching the Pechora Sea. Until now, things had been going quite well. Ten days had taken them from Hamburg around the Scandinavian peninsula and most of the way across the Barents Sea. Thanks to a judicious combination of sail and engines, they had averaged about two hundred miles a day. They had maneuvered around icebergs before, but so far the icebreaking aspect of the Catherine the Great’s design hadn’t come into play. Those thoughts were enough to take Vladimir from the wardroom to the bridge, and as he looked out over the wide white expanse of ice he realized that was about to change. The ice floe was at least two kilometers across.
Captain Adams started giving orders and men in heavy coats moved out onto the deck. They had drilled for this, but never done it for real till now. The sails were reefed and the treads engaged. Each tread was like a large tractor tread, save that it had a series of paddles attached. As the tread moved, the paddle pushed against the water. A propeller gets its force by pushing a little bit of water very fast. A paddle, whether it’s in the hands of a kayaker, on a paddle wheel, or attached to a continuous track, gets its force by pushing against much more water at a much lower speed. The difference was somewhat analogous to the difference between an internal combustion engine and a steam engine. The internal combustion engine needs speed to work well. The steam engine can have much lower horsepower, but still have greater torque. Eight paddles, four on each tread, were in the water at once. They were two and a half feet deep and five feet wide. That’s a hundred square feet of ocean to push against. Even at very low velocity, they pushed the Catherine the Great forward with tremendous force.
Captain Adams flipped a switch and ordered, “Stations, report.” He got reports back in order, a lookout at the bow, the engine room and boilers, the port and starboard tread watch, and others.
“Slow ahead,” he ordered the engine room.
The bow touched the ice floe, and kept right on going, pushing up onto the ice and applying increasing weight to the ice. The false keel concentrated that weight on a small area, and the ice broke. The shape of the hull pushed the ice down and to the side, stressing the sheet of ice as the bow moved on into the ice. Thus breaking up more ice, which got pushed to the side and under the surrounding ice.
Captain Adams ordered more speed and the bow of the Catherine slid higher on the ice. Then they got a report from the treads. “Churning water.”
Churning water was the paddle equivalent of cavitation on a propeller. It was almost a constant on a paddle wheel, where the paddles were constantly going into and out of the water. But for a paddle track where the paddles went into the water and stayed in the water for the length of the track assembly, churning water meant a loss of efficiency—less of the power of the engines used to push the ship and more of it wasted, churning the water. Not surprisingly, as they broke ice they faced greater resistance. The paddles started churning at a lower speed.
Captain Adams ordered them back to slow ahead and the churning decreased. They were lucky to make a couple of knots. But, for almost an hour, everything went according to plan.
Then a chunk of ice, five feet long, six feet wide, and three feet thick, popped up where the starboard tread was dragging a paddle into the water.
Each paddle had support wedges, three on each side. They rested against the tread and kept the paddle close to perpendicular to the tread. The paddle was not weak. It was two-inch thick oak, plus the supports and backing. It broke the chunk of ice quite nicely, but that wasn’t the first piece of ice that paddle had faced. It had been ripping up chunks of ice for over an hour and every chunk of ice it hit, hit it back with equal force. This was one whack too many and the outboard support wedge broke. That added a diagonal stress to the paddle and the middle support wedge cracked. More importantly, the stress on the lock bar on the outboard section was suddenly a twisting stress. The tread kept moving and the paddle made most of its transit before it ripped loose.
As the tread pulled the paddle up out of the water, the damage became apparent and the call to stop the treads was given.
Captain Adams picked up his Grantville-made galalith plastic phone handset and pushed the button that connected him to the starboard tread watch. “What’s wrong?”
“We have a paddle loose and dragging, Captain,” said Engineer’s Mate Guy Sayyeau. “It’s ripped loose and is halfway to hitting the next paddle.”
Captain Adams looked out at the ice floe. They were perhaps a hundred yards from open water. “Can you knock it loose?”
“Should be able to, Skipper,” Guy said in Dutch-accented Amideutsch. “Take maybe five minutes.”
“Do it then. We’ll see about full repairs when we’re out of the ice.”
Guy climbed out of the small compartment that was his duty station when the paddle treads were operating. He used a harness and rope on pulleys as a safety measure, but he climbed down a ladder to the continuous track. It was five feet wide and twenty long, with a front power wheel, ten road wheels, and five return rollers. It was also freezing even as he watched.
Franz Heuber handed him a ten-pound sledge hammer once he was standing on the track. Guy walked along the track, climbing over paddles to get to the broken one. The paddle was attached to the tread by three one-inch diameter oak dowels that attached at the ends and the middle. The outboard dowel had been shredded by the force of the ice impacting the paddle. That wasn’t the problem, as it turned out. The problem was the middle dowel. It was still there, but it was wedged in and there wasn’t enough of it showing that he could reach it to pound the damn thing loose. “Hand me down a punch. No. Franz, you’re gonna have to come down here and hold it.”
“Wait a moment,” said another voice, the husky raspy voice of Valeriya Zakharovna. “I’ll bring it.”
Guy looked up at Franz and shrugged. Valeriya had been working with the crew of the Cath since before the icebreaker sailed out of Hamburg. She was big and strong, and no one wanted to argue with her. Franz called her the Aristotelian ideal of bosons, but Franz was proud of his flowery language. Guy…he just liked a woman he could look up to. Guy was a strong man, but not tall. He stood only five feet six inches. He had curly, sandy brown hair that was never in place and often matted. He had survived smallpox as a boy and it had left its mark on his face. But he had come to understand steam and the chain drives on the Cath and had been working on it from the beginning.
Franz stepped out of the way. Valeriya reached up to the grab bar and pulled herself up and through the porthole, then lowered herself onto the tread. Guy noticed the way she moved and was distracted. But once she was down, he looked away and focused on the broken paddle.
Guy whacked at the paddle with the sledge, trying to get it loose. He busted it up some, but couldn’t get it free.
“Hold up, Guy!” Valeriya shouted. “Let me set the punch.”
Guy stepped back and Valeriya set the three-quarter inch punch in place, then held it while Guy hammered. It took only a couple of minutes to pound it loose. That stressed the inboard dowel, so they had to use the punch again and they ran into a design flaw.
“This should be farther outboard,” Valeriya complained.
“Or it should be designed to punch out the other way,” Guy agreed.
The placement wasn’t a problem if you were using an ordinary hammer, but a t
en-pound sledge needs swinging room. Unfortunately, the inboard portion of the tread was less than a foot from the side of the hull. They should have either had the dowel more offset from the side of the track or made it so that it could be punched out in either direction. By the time they were done, the whole continuous track assemblage was glued together with a thin layer of ice. It took ten minutes of pounding and two buckets of boiling water to get it loose.
By that time there was a thin layer of ice surrounding the ship. It was very thin, a sixteenth of an inch or so, and in and of itself didn’t represent much of a problem. However, it indicated that if they had to stop for any appreciable time to make repairs, they could find themselves frozen in place. The placement of the paddles was based on tests using models to measure force. Losing one meant less force, so the starboard tread had to run faster to compensate. They also had to back up a bit and get a running start. All in all, they lost close to an hour. Not too bad, considering that even in open water with sail and tread they rarely topped ten knots.
By the time they were through the ice floe and back in relatively clear water, they all had a much better idea of the sort of trouble they were going to face on the trip.
For the next seven days, Catherine the Great traveled much more slowly. They rarely used the sails. It seemed to Vladimir that they would exit one ice floe then run into another.
Yesterday they had spent the whole day and night breaking ice. The Catherine was a good size ship for the seventeenth century, and very solidly built. She had broken through the ice quite well, actually better than expected. There had only been a few times when they had to back up and ram a floe repeatedly to break through. The hull and false keel were both holding up well but they had broken more paddles than they had expected.