Chapter 17

When Empire Builder was ready to be returned to the work shop, Charles discovered an most egregious blunder: he had forgotten to provide for driving in reverse! He had not bothered to install any brakes, as he didn't think that brakes would be necessary on this first trial, so they coasted past the loading ramp. Oops! No way to back up. Charles and Big Bull had to dismount and push Empire Builder back about 20 feet to get it lined up with the ramp so that it could be driven up. Oh, well, live and learn!

Charles worked out a new arrangement for the drive belt so that they could travel in reverse when they needed to, though the change over for a new direction of travel was too tedious to be completely practical. It took three days to get the new "transmission" and brakes installed, so they were delayed a bit in doing their pulling tests. When they were ready, they hooked a wagon behind Empire Builder and invited people to climb on for a test ride. The passengers were warned that a few might have to dismount if the load became too great for the tractor to accommodate, but nobody cared. They quickly got a full load for the first run, and off they went without difficulty. The trailer was loaded with 15 people, so Charles guessed that they were pulling at least 1800 pounds, when you counted the weight of the wagon, itself. This was more than a single camel could possibly do, and really more than a team of two camels should be asked to do—a very gratifying result!

There was some slippage in the drive belts, so Charles was anxious to see what could be done with gears instead of leather belts. They spent the day giving rides to the community while Charles looked for other bugs that he needed to address. He did see that the trailer also needed brakes, so they would need a crewman on that wagon to operate the second set of brakes. At this point, he did not see anything else that required his attention, except that the trailer also needed springs.

Charles applied almost all of his attention to the problem of a geared transmission for Empire Builder, Mark II. This took two months to resolve, since he had to build a wooden prototype to be sure that everything worked as it should. He followed his father's advice and provided a clutch mechanism between the transmission and the drive wheels. Finally, they were ready for the next trial run, and, as before, the entire town turned out for the demonstration. There was only one forward gear and one reverse gear; they did not need anything more elaborate than that at this stage.

An initial run was made with one trailer and no passengers. That was successful, so they hooked a second trailer up in tandem. When that worked fine, they invited people for a ride. The first ride was with people only on the front wagon, and the rear wagon was left empty. As before, 15 people climbed into the first trailer, and the tractor was able to pull that and the empty trailer with no difficulty.

In a fit of uncharacteristic caution, Charles loaded only five people into the second wagon, so that the total load was 20 passengers. The tractor showed a noticeable strain when pulling this much weight, but managed to do it. With this success, Charles allowed five more people to climb aboard the second wagon. Again, the tractor showed the effect of the added weight, but managed to pull that much, despite the signs of strain. However, when they went to a total of 30 passengers, they never moved. They made several tries, but, either the motor stalled, or the drive wheels slipped.

They tried reducing the load, one person at a time, until the tractor could pull the load. They found that they could barely pull a load of 27 passengers, but not 28. Charles estimated a total load of 3,000 pounds, which was well beyond what he had expected, so he was quite happy.

As a final experiment, he loaded the last trailer to capacity of 15 passengers and put no load in the first trailer. This load was easy to pull until they got to the turn around point. When Big Bull turned the tractor, the first trailer turned over. Charles had expected this to happen, which is why he had saved this experiment for last. The passengers helped right the tipped trailer, and they all rode back to the starting point in the front trailer.

Back at the ramp, the passengers got out, and Empire Builder II pulled the two empty trailers up the ramp with the air of a conquering hero. There was a lot of cheering and applause, plus the settling of a number of wagers.

The next question to settle was what kind of fuel mileage could they expect. The next day, they measured how far they could run on one gallon of fuel when they were not pulling a load. The answer was 37 miles per gallon. Next, they loaded the two trailers with rocks to the maximum and measured again. This time, they got 23 miles per gallon. Now they knew how much fuel they had to take to make an extended trip. Clearly, they were going to have to establish refueling points along the way to be safe.

They had to travel about 200 miles for each of the three metals, and, to be safe, they had better figure on about 15 miles per gallon, so they would need approximately 13-14 gallons of fuel each way. At an average of five miles per hour and a 10-hour day, that 200 miles will take four days. Better figure on five days just to be sure. In summary, put a 20-gallon tank on the tractor, and take four 10-gallon spares, one to be cached at about 73 miles and the other at about 146 miles. These would be the emergency supplies for the trip home.

The next thing they needed was more engines. Charles set out to build four of them and to train four engineers in every detail of maintenance and repair. Charles would make the first long trip of each new tractor as the brakeman, but normally, he would not go along, since he was too valuable to lose to accident or worse.

The four tractors and associated trailers were built over the next six months, so they were ready to go as soon as the snow melted enough for them to get through.

As a further safety measure, a double-size crossbow was designed and built with a steel bow and a wire bowstring. While everything else was going on, an engineer had come up with the tools necessary to draw fine wire from steel, so they now had a reliable bowstring that would not stretch in wet weather. Oversize darts were made with broadhead points made of hardened bronze. The crossbow was mounted on a tripod on the tractor bed, and it was truly an awesome weapon. A total of 50 darts were made for each of the four crossbows, and these were sure to stop anything that walked on two or four feet.

Flower of Spring had spent most of her time trying to make glass for lab ware. She wanted to make an equivalent of the Pyrex that Doug had told her about, but she just could not get the high temperature required. She had made a serviceable glass and was able to make test tubes, beakers, and flasks after a fashion, but she was really not that skilled at glass blowing. Most of the stuff she made came out lopsided, so she looked around for someone to help her.

She found a young man nearly her own age who quickly developed a knack for making what she wanted. He could even blow flasks without a mold to remarkably uniform volume. She provided him with raw glass, and he made laboratory ware for her. They saw each other quite often, because the "soft" glass of her laboratory ware broke very easily, and she was continually having to replace it.

She was able to get a fairly high temperature from a Bunsen burner that Charles designed for her. It burned the same methane that the light fixtures used, so she had no trouble with a supply of fuel. She had a small supply of compressed air that she could use to get a little more heat, but she really needed oxygen to get very elevated heat. An oxygen/methane fire would get pretty damned hot, but she could not yet make pure oxygen. Maybe Charles could modify a heat pump so that she could get air cold enough to trap the oxygen, but she was sure that was years away.

All she knew about Pyrex was that it contained boron, a component of borax. They could get borax if they were willing to travel far enough for it, but that, too, was impractical at this time. She did not know enough about borax to know if that would help her, so she just let that problem slide, along with a myriad of other lab and chemical problems that she could do nothing about right now.