Getting the limelights going was another job of bucket chemistry. I had some iron grids cast that would fit in the bottom of one of our beehive coke ovens, to raise the coal off the bottom so we could run water underneath. While that was being done, work was started on the gas tower, a circular water tank in which floated a vast close-fitting, copper-lined, straight-sided barrel. Not that a straight-sided barrel was unusual. They were the only kind in use until I introduced the potbellied variety and proved that they leaked less.
Pipes went under the tank and up to just above the waterline. When gas was produced, the barrel rose, to settle again as the gas was consumed.
How big a gas tower did we need? How much gas was needed to keep a limelight going? Was one coke oven enough? Too much? I hadn't the slightest idea. I just made things big and hoped for the best.
Then, too, I'd never even seen a limelight, I'd only heard about them. As I understood it, it was a hydrogen flame under a lump of lime. I didn't know what sort of a burner was used, so I used a bunsen burner.
Six weeks and eighteen thousand man-hours later, seventy-five tons of coal was loaded into the converted beehive coke oven and lit on fire. It was necessary to have the grid completely covered with coal so that the steam would be forced through the coals rather than around them.
The system worked to the extent of generating a flammable gas, and filling the gas tower, but the faint blue flame produced was hot enough to heat the lime only to a dull red. Not a very efficient light, which was the purpose of the exercise.
I could think of only two ways to get a hotter flame. One was to use pure oxygen instead of air, since the nitrogen in the air cools a fire considerably. The trouble with that was that I didn't have a good source of oxygen, and we weren't quite up to building an air liquefaction plant.
Oh, I could have heated mercury, a remarkably cheap substance in the Middle Ages. It was an industrial waste product from the manufacture of sulfur. At moderate temperatures, mercury absorbs oxygen and at higher temperatures, gives it off. But having that much mercury vapor around was scary. At least with carbon monoxide you know when you're being poisoned. I'd save the mercury scheme for a last resort, if then.
The other way was to preheat the air and gas before they were burned. I spent a few frustrating weeks getting a burner of this sort going. The trick turned out to be to mix clay with slaked lime and mold the heat exchangers into the lamp itself, then run it through the brick kiln to harden it. A few months later it was discovered that a fire clay lamp painted with slaked lime was stronger and brighter. One problem with this scheme was that it required pressurized air, and thus a second set of pipes running to each lamp. But at least it didn't need a second fancy locked valve at each installation.
But by the time the new lamps were ready, the weather had closed in and the water under the gas tower froze. In normal operation, this wouldn't happen because the gases themselves would be hot enough to keep the water liquid in the worst weather, but we had shut the system down while I worked on the lamp. We drained the water, covered the tower with straw and circulated hot coke oven gas through it until the crust of ice was melted. Then we started over.
This time the lamp got to a fairly bright orange after an hour or so, and I declared that to be good enough.
Other things were going on while I was playing with lights. Zoltan's people started doing us some good. Their pottery man came up with five colors of glazes made from local materials, and we went into production making tableware, at first for ourselves, but then for sale as well.
Their papermaker was in limited production turning our old linens into very nice rag paper.
And their sword-maker was screaming at the top of his lungs at Ilya, who was naturally screaming back at him, both men being of the opinion that sufficient volume could make up for their lack of a mutual vocabulary. The workers had a betting pool going on which one would kill the other first, and at what time of the day this happy event would take place.
The two smiths went on screaming for over a month with nothing accomplished, so I had to step in and demand that the sword-maker demonstrate to us his methods. They surprised me, being nothing like the Japanese method I'd told Ilya about two years before.
He collected up a pile of wrought iron and beat and cut it into small pieces, about the size of a ten zloty piece, or an American quarter. He put a measured amount of this iron into each of a dozen round bottom clay flasks and packed them full with raw wool, Then he sealed the flasks and took them up into the hills where it was quiet. He built a fire around the flasks and after a day of burning he started gently shaking the flasks and listening carefully. When the metal inside "sounded wet," he let the fire go out. On breaking open the flasks, there was a fused blob of steel inside he called "wootz." This he worked at relatively low temperatures — never red hot-until it was shaped like a sword or knife. Then he hardened and tempered it in the usual manner. The result was watered steel that looked just like the steel in my sword, and kept a fine edge.
It wasn't quite as good as my sword, however. I pared the edge off one of his knives with my blade, which had the swordsmith staring goggle-eyed. None the less, it was better than anything Ilya had done using the method I'd told him about, so we went into production using the wootz method.
The glassmaker started to make glass out of sand, lime, and wood ashes. After having him make a very fancy drinking glass as a Christmas present for Count Lambert, I had him make a chimney for the gas lamp, to conduct the fumes away. The chimney made a great improvement in light output, and it took me a while to figure out that the glass was transparent to visible light, but opaque to infrared, which was reflected back to the lime, making it hotter.
All of which shows that it isn't necessary to know what you're doing in order to be able to accomplish something. It's only necessary to be sufficiently persistent. Sort of like the infinite number of monkeys at an infinite number of word processors who wrote everything in existence.
Anyway, we now had good light source, and I gave orders to plumb the factories and furnace areas, and had two gross of the lamps made. By spring, we had light as long as we wanted it, by which time there were eighteen hours a day of sunlight, and we didn't much need the lights.
But next winter…
The shops weren't idle either. We made a rolling mill to make sheet brass, and some small punch presses to use the sheetmetal. I designed some simple door locks and padlocks, and they looked to be a profitable line.
Our reinvestment rate was over ninety percent. That is to say, most of the things we made were for use in our factory system. But we still needed to buy a fair amount of stuff from the outside, and additional cash was always welcome.
Transportation costs were very high in the Middle Ages, especially for land transport. The best mules can only carry a quarter of a ton, can only go thirty miles a day, and must be loaded and unloaded by hand twice a day. Expensive.
This meant that the most profitable products would be small, light, and valuable. Locks, glassware, pottery, cast-iron kitchen products, plumbing parts, and clocks were all being made by spring, as well as our older brass works' lines of church bells, windmill parts, hinges, and other hardware. I wanted to add paper, printed books, and cigarette lighters in the near future.
We expanded the paperworks from a two-man outfit to one where a dozen men worked, and added power machinery to cut and mash the linen rags to pulp. Within the year we added a papermaking machine, which was a major undertaking but not a major headache. I'd at least seen a papermaking machine.