All Aboard Florida shows why private passenger rail is still a victim of hostile government

(Note - I'm strictly non-ideological when it comes to how to provide a quality passenger train. For profit? Government subsidized? Don't care. I just care it happens. This rant will concentrate on attacking those who demand profits for their apparent complete silence when it comes to a railroad that's trying to do exactly that.)

Given the attacks on Amtrak by the "free market" right over the years, and their insistence that passenger rail only failed in the US because of market forces, and nothing else, you'd think they'd be jumping on the FEC's All Aboard Florida project as a chance to show "how it should be done", lobbying for pro-rail policies in Florida that do everything except issue a subsidy.

In particular, you would assume:

• Land that's State owned, unused, only suitable for right of way use, and less likely to be necessary for future expansion if a train is taking passengers off the roads, should be made available to the railroad at low cost.
• The system of taxes, levies, etc, waged against railroads that seemed relevant in 1902 when trains were the only viable means of medium/long distance travel should be reformed so passenger trains aren't subsidizing cars and airports.
• Given that choice is supposedly a keystone of a free market, and given rail is actively harmed by a lack of choice, you'd expect planning reforms from communities wanting in on a private train service.

Those are three Pretty Big Deals. The first is necessary because private passenger systems are unlikely to succeed if they're limited to travelling on existing rail lines, especially given the massive cuts in routage the national system has suffered in the last 100 years. Case in point - there's only one line, owned by CSX, that goes from West Palm Beach to Orlando, which is a connection the FEC wants to make.

The second is ridiculous: it remains the case today that passenger systems are essentially punished by the tax code. I don't mean that in a "I'm a billionaire and I have to pay a 30% tax rate boo-hoo I'm being punished leave job creators aloooooooooooone!" sense, I mean actually punished - railroads provide a service, and they're penalized for doing so. How?

Well, passenger rail, whether used or not, adds value to local communities. By all accounts, a neighborhood's property values increase by approximately 80% compared to similar neighborhoods, if connected to a rapid transit system. But this happens regardless of how well the system is used. People like having a train available, and are prepared to pay higher property premiums (and, uh, property taxes - take note) to live in a place that's connected, even if they don't plan to use the train on a regular basis.

Couple this with current planning laws, where all new (since the 1950s) neighborhoods are built such that usage of a car to transport yourself is all but mandatory, and you reduce the chance that any passenger system will ever be able to pay for itself. Most passenger services have, and always have had, low margins. Requiring any passenger service that's desired by local residents, but not heavily used, to pay high taxes for its infrastructure, makes it much harder to succeed as a private for-profit enterprise. And this is in large part why most railroads went freight only in the 1970s. Shooting a freight line through a neighborhood damages that neighborhood's value rather than increases it, which reduces the taxable value of much of the infrastructure owned by the railroad located there, as well as requiring less infrastructure (typically well used passenger lines need to be double tracked) to be taxed in the first place.

The State seems dysfunctional

So, the State of Florida, which suffered an abrupt end to the FEC's passenger service in 1969, and everything else in 1971, thanks in large part to hostile rail policies, has learned its lesson, right? Right?

I'm not going to say the State doesn't get it completely. They're relenting on the aforementioned stupid car-only planning policies from Jupiter to Miami, but otherwise they appear to be looking at All Aboard Florida not as a chance to relieve themselves of some of the burden of providing transportation infrastructure, but as a chance to make a fast buck.

The FEC needs a right of way to get it to Orlando. For decades the FLDOT has had such a right of way available, making it clear that part of the land currently adjacent to I-4 and various turnpikes was intended for rail use, publishing maps describing this.

Nobody else has expressed any interest in building a railroad on these rights-of-way, and the FLDOT even, when the FEC made a request to use the line, opened up the proposal to ask for counter offers. Which is right. They should have done. But there weren't any.

So, the FEC's getting the land for free, right? Or perhaps for a nominal charge like $1, or $1 + a $500 filing fee?

Well, no, staggeringly the amount of cash the FEC is paying varies, but at least one portion will cost over $275,000 a year. There's no suggestion property taxes are being reformed.

But the bit that stunned me is that All Aboard Florida will actually pay one of the turnpikes - yes, turnpikes, owned by the State of Florida - compensation for lost revenues caused by people choosing to take a train instead of driving.

There's no suggestion property taxes are being reformed. So essentially the State wants AAF to increase the extent to which passenger trains subsidize car owners, not decrease it recognizing that passenger trains inherently reduce costs for road infrastructure.

There were plenty of articles when the service was being proposed about local politicians up and down Florida's Treasure Coast, where I live, and an area through which the FEC passes through, excitedly requesting the service serve us because, you know, c'mon! There's a lot of us, and we'd like to use it too. And I know it's not going to happen. It just isn't. It's not that the FEC couldn't get enough of us to use it to cover the direct costs of providing stations here (and presumably additional trains because you don't want the main Miami-Orlando service to be slower), it's that the amount of additional revenue would be slight, and the effect on its tax burden massive.

And those same politicians aren't actually instituting reforms that would increase the number of passengers. I'm not seeing a single Martin County politician who's taking concrete steps to end suburban sprawl - indeed, Martin County's "slow growth" policy has always been anti-urban, with bans on buildings four stories high, and with the usual parking mandates and mixed development bans that prevent walkable communities from ever happening. Martin County is a cluster of HOA-controlled "communities" and strip-malls, as a matter of public policy. Why would a politician who refuses to change that think that a private train company would be remotely interested in serving that community?

But they're going ahead anyway

Despite the ludicrous attitude of the government, All Aboard Florida is still on track, so to speak. And good for them. They expected it to make a large amount of money, and they're looking at a million here, a million there, etc, as relatively minor in the great scheme of things. But without significant reforms, AAF isn't going to be a demonstration that private rail service works. AAF will, at best, prove that certain types of express service can be profitable and unsubsidized. AAF will be able to link large transit-served population centers, separated from one another by long distances. 

Meanwhile I'm not hearing criticism of the demands that AAF find additional ways to subsidize car owners, that existing subsidies for the roads from railroads be lightened, and that planning laws continue to prevent people from using any form of transportation other than cars in most of Florida. Why the silence?

Culture of danger

I'm a little staggered by the fallout over the accident at Lac-Mégantic.

In theory, most of what happened is open and shut. An accident happened - a tragic disastrous accident - when an unattended train rolled away and derailed in the middle of a city with its cargo catching fire.The CEO of the railroad has claimed the engineer that was responsible for the entire train failed to set the correct number of handbrakes before leaving the train, thus, accident.

Of course, "thus accident" is never that simple. The train was:

• Unattended
• On the main line
• Using substandard equipment to carry the cargo
• Had a locomotive that was in such a bad state of disrepair that it was noticeably on fire within 15 minutes of the engineer leaving it - and reportedly the engineer said it was a problem to his taxi driver when he left it.

Were any of the above not true, the accident wouldn't have happened. Accidents are rarely caused by one thing going wrong.

• If the train were attended, steps would have been taken as soon as the train started to roll to stop it
• If the train hadn't been on the main line, the train wouldn't have gone anywhere.
• If the DOT-111 tankers had been replaced by more modern equipment, the derail would be unlikely to have been as lethal, as it would have been highly unlikely a fire would have broken out.
• Had the locomotive not caught fire, it wouldn't have been turned off, which means the airbrakes would have held, and the train would have stayed in place.

The CEO's attempts to point the finger at his engineer are far from reasonable either. The engineer in question knew his train was going to be taken over by a different "crew" later on that night. So it's reasonable to ask the question: if the CEO is right, and the engineer was that irresponsible, why did he not expect to be caught by his relief? Put yourself in the shoes of the relief "crew" (is it really a crew if you're one person?), you get to the train, the lead locomotive is a mess, and you go to disengage the handbrakes only to find there aren't any engaged. Are you seriously not angered enough by such a disregard for basic safety that you can't be bothered to report this?

Is this what bothers me? Kinda. But what's equally troubling is the rail establishment's reaction. Because apparently everyone knows "Ed" - Ed Burkhardt, the CEO of Rail World, the company that owns MM&A, the railroad that executed this tragedy. And if there's one thing they all know, it's this: you guys should Leave Ed Allllllllllloooooooonnnnnee.

Burkhardt is an interesting character. He's a long time railroad professional, and apparently has rescued more than one railroad from a likely grave. MM&A is just one of his latest projects. While I don't know him personally, I have to say based upon everything from Rail World's website (which might as well be called Ed Burkhardt .com) to his decision to wait a week before going to Canada because he wanted to work out all the insurance details himself, personally, that he comes across as a bit of a micromanager. Perhaps he isn't. But certainly as the head of a railroad, as a lead proponent of some of the policies - like the one man crew issue - that are now being questioned, it's hard to suggest that, well, he's not at all responsible for what happened. And it's definitely hard to see why people shouldn't actually criticize Burkhardt's response given it's difficult to separate him and the culture that caused the accident. BP's Tony Haywood could be reasonably held blameless, he wasn't in charge of BP long enough or close enough to the people involved, to be considered responsible for the Deepwater Horizon Gulf oil spill, and yet poor Tony was slammed for his response to that disaster. Meanwhile, this arguably bigger tragedy has people actually claiming the CEO is being treated terribly unfairly.

So why's he being defended? And so forcefully? A clue lies in the general response to one of the counts against MM&A. The media has been trumpeting the fact that the MM&A has a below average safety record, and it does, it has an accident rate more than twice the average.

Burkhardt's defenders point out that's misleading. They say that short lines do, typically, have much higher accident rates than average. MM&A isn't actually a short line, it's actually larger than many major Class 2s such as the FEC, but I suspect the point they're making isn't about size but liquidity and financial health. The MM&A is having trouble making profits, they say, and so its safety record needs to be compared to other railroads on shoestring budgets rather than, uh, the FEC.

Another clue, perhaps, is in why people like Burkhardt are popular to begin with. Trains Magazine's Fred Frailey posts a highly positive profile of another CEO, the Illinois Central's Harry Bruce, in the latest issue. Why Bruce? Because Bruce reportedly rescued the IC using some highly exciting (not really) corporate restructuring leaving most of railroad functional afterwards. Nothing wrong with that, of course, I'm just pointing out that's what's important.

I'm going to say it: what Burkhardt's defenders appear to be coming from is that in this industry it may be necessary to cut corners, but as long as you're doing so to keep a railroad alive, you have your heart in the right place.

I don't think that's right. And I grew up in Britain in the 1970s and 1980s where the worst people since Hitler were Myra Hindley (a serial killer), Ian Bradey (another serial killer and Hindley's co-conspirator), and Doctor Richard Beeching (someone who successfully proposed cutting 1/3 of Britain's railway network.)

And what concerns me more than anything else is that this might be the attitude of the rail establishment within the US. It's certainly easier to explain the anger at Burkhardt's critics if you believe that MM&A's policies and culture is typical of mainstream railroading.

(It might even be easier to explain things like the FRA's ludicrous over-the-top passenger rolling stock requirements if you assume the FRA, after decades of experience, just doesn't trust the railroads to give safety a passing thought.)

Using systematic corruption for good

Some years ago, I had an epiphany about John Major, Britain's first post-Thatcher Prime Minister. One of Major's signature achievements was the privatization of British Rail, Britain's battered state-owned railway company.

British Rail was a textbook example of how taking an industry into state ownership and then subsidizing it can cause it much harm. Originally intended to be profitable, the Government panicked after it made large losses for a few years in a row in the 1950s. A corrupt Minister of Transport, Ernest Marples, appointed a commission to look into BR's problems, and then appointed a contrarian member, who'd argued for BR receiving a lobotomy to return it to profitability, to take charge of the business itself. That man was Richard Beeching, and his cuts proved to be disastrous, causing a once universal rail system to drastically reduce in usefulness. The cuts did nothing to reduce British Rail's losses, indeed, I'd argue that they caused them to continue, when BR was in the midst of modernizing a network whose problem was more the high cost of maintenance than a lack of demand for services.

A second attempt, in the 1980s, to cut British Rail, was in some ways foiled precisely because Beeching's cuts were discredited. But there was no guarantee that this would continue, with the Thatcher government generally being rail hostile, and the risk of another corrupt minister deliberately undermining the rail system.

The British railway system is a critical part of British infrastructure, and it's virtually impossible to imagine the UK continuing without it. Roads of any size are overloaded, cities are too crowded to allow for every resident to own a car (just finding a parking spot outside of your own home is a rare luxury few enjoy.) And, quite honestly, public transport is pleasant. It's not perfect, but the view in America of buses being something you get mugged on, for example, which itself is ridiculous, is considered laughable.

And with environmental concerns about road based transport, as well as the oil dependency issues it raises (taken more seriously in the UK than US, where high gas taxes exist to attempt to prevent repeats of the 1970s), it's as much a national security issue that the rail system exist and be useful to passenger and freight alike as it is a practical issue.

So "something had to be done", and John Major, to give him credit, did something - intentionally or otherwise - that I think is pretty good: he used the corruption of government against itself.

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Now, at this point, you can probably guess this is a kinda follow on to my last JE. In the UK, just like the US, there's a corruption in government. In the US, it's more obvious and arguably more tolerated. It's just assumed that you can buy influence, and to a certain extent people informing themselves about politicians vote in part based upon who's sponsoring them, rather than against them because they're being sponsored at all.

The UK has two major parties, the Conservatives, who are owned by the business community, and Labour, who are owned by the unions. The union ownership is largely uncontroversial - unions exist to represent their members, who are ordinary people, so giving them representation within government doesn't seem evil. But it should be kept in mind that this doesn't mean Labour does the right or most democratic things because of that: consider, for example, whether given the choice between an environmentally correct choice, and one that protects the jobs of coal miners, the system is set up to ensure Labour makes the right decision.

Now, Ernest Marples, above, owned a road haulage company, taking steps to disguise his continuing ownership of the company when he was in power. The biggest threat to road haulage was British Rail, which operated a relatively open freight and light freight network. Since the Beeching re-organization, routes have been cut, and the bars for being able to use the freight network have been drastically raised. So Marples directly benefited from his choice of Beeching to manage BR. But that's not all that was going on.

Let's look at the situation in the 1960s.

• British Railways was a branch of government. It couldn't lobby for itself, in the sense of making campaign contributions and aiding the election of friendly candidates
• The road haulage industry could lobby for itself, and did, causing the Conservatives to become anti-rail.
• The car industry could lobby for itself, and did, also causing the Conservatives to become anti-rail.
• The car industry and road haulage industries could also lobby non-political, but influential, entities like the media, a route not available to the state-owned rail company.
• The unions were split between the road haulage industry and the rail industry. Labour therefore followed the path of least resistance, which was to continue what was already in place. That meant implementing Beeching's cuts.

How do you protect British Rail (or rather, the railway system) going forward? Well, the only way is to build a counterweight to the road industry. 

• You create businesses that rely upon the existence of the railway system to survive.
• You bring in companies that would otherwise be rail hostile, such as other transportation companies, and make them reliant upon railway income.
• You ensure the subsidy system is not open to question, by creating mechanisms that at least suggest that if it were possible to run a system for less, the subsidies would be less.

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John Major's privatization of British Rail looks exactly like what you'd expect it to look like based on a "Protecting the railway" agenda above.

1. You create businesses that rely upon the existence of the railway system to survive.

British Rail itself ceased to exist in the privatization, but several corporations were set up to manage the actual infrastructure and own British Rail's former rolling stock. One of these, Railtrack, the company that managed the infrastructure, was controversial from the start and was eventually brought back into national ownership, and arguably this is the one part of British Rail that should have remained nationalized.

2. You bring in companies that would otherwise be rail hostile

British Rail's operations were devolved into a set of franchises. Companies were invited to bid on each franchise, with the winner given a semi-monopoly on services covered by that franchise. BR's competitors were specifically encouraged to take part, and they did. Bus companies National Express and Stagecoach were involved from the start, as was Virgin, owners of Virgin Atlantic.

Suddenly companies that were competing with the rail network, were now directly benefiting from it. They had no reason to lobby against the network, and indeed had good reasons to argue for more government support.

3. You ensure the subsidy system is not open to question

While, to the surprise of some I guess, large parts of the rail system are profitable, many parts aren't, and so part of the process of picking companies to run franchises involves requiring each business bid on a subsidy (or lack of one.) The company that has the most positive effect on the Treasury, while being competent and able to run the services required, gets the franchise.

This makes it much more difficult to suggest that parts of the network are over-subsidized. If it were possible to run a serviceable train system for that franchise for much less of a subsidy, the company that bid on it would have been out bid.

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So there you have it. Corruption used against itself. To be fair, the current British railway system is far from perfect, and there are a lot of complaints about the privatized system. Still, travel on it is astonishing cheap compared to 15 years ago, there are more services, and more frequent services, and most agree it's still the best way to get around Britain.

Moreover, Beeching is finally being undone. Train operating companies are demanding new lines be built, often to replace lines that Beeching killed. Until the privatization, there was virtually no entity with power capable of lobbying for those new lines, and still less any chance of them ever happening.

Other countries might learn a thing or two from what Major did. I'd like to see something similar in the US, with state owned rails, and privately owned trains. This would, at the very least, remove some of the inequities that make running passenger trains in the US so unprofitable, such as the absurd property taxes. And it would create "Big Train", a lobby that'd argue for expansion of the network. Unfortunately, legally and morally, it would be immensely difficult to do such a thing. The right time would have been with the break-up of Conrail, or even at the formation of Amtrak, but the concept of "Private lines, public trains" is so embedded in the US rail system it would be difficult to undo.

Steam vs Diesel

I thought I'd get away from politics for a moment and write something else that happens to include two of my favorite subjects: trains, and Civilization (the game, that is.) Well, it's just a thought process that hit me this morning, while I was driving to work and I was trying to figure out the relative complexity of a stream engine, and an internal combustion engine.

The question morphed into "Why was the steam engine invented when it was, and not the entirely different internal combustion engine?" To which a bunch of answers suddenly come together that then expand into a big cloud of explanationness. Answers to questions like "What's with the big wheels?", "Where the gears at?", and "Coal? Srsly?"

How this fits into Civilization is this. Civ is based upon the fact that technologies cannot exist until other technologies they depend upon exist. I figured it was possible to do an analysis to determine why each were invented when they were invented.

So, let's begin, and I'm going to begin with some pictures demonstrating a locomotive type:

Here's a steam engine that uses this layout:

This is what's called a "Pacific", the term doesn't refer to any specific locomotive, but rather a class of steam locomotives that have a particular wheel layout. They're also classified as "4-6-2", which means "four non-driving wheels at the front, six driving wheels in the middle, and two at the end." (If you're thinking "Shouldn't it be 2-3-1?" - think "two rows of wheels, one on each side") The tender isn't included in this. I'm picking on the Pacific because, well, it's a good example of all of the elements that made up a classic stream locomotive just before everyone switched to electric and diesel. In some ways, it's a great big kludge, a collection of hacks designed to make the thing work with contemporary speed and power requirements - but that's not a nice thing to say, and most train enthusiasts would want to smack me for saying that, because the vast majority of Pacifics were beautiful machines.

Anyway, notice the following elements:

• Big driving wheels, attached directly to the body of the locomotive.
• More, smaller, wheels at the front and back
• A transmission that involves big long metal rods pushing and pulling things. There are no gears. None whatsoever.

For comparison, here's a fairly typical diesel locomotive:

This is what's known as a Co-Co diesel locomotive. It has nothing to do with Conan. All that means is that it has two trucks (American terminology, and what I'll use from here on) or bogies (British terminology, also slang for dried mucus), each with six wheels (three per side), all of which are driven wheels (wheels connected to an engine.) Engines with four wheels per truck are also common, and are called Bo-Bos.

How a diesel driven vehicle transmits motion to the wheels differs from application to application. For road vehicles (ie cars, trucks), and for a type of train called a Diesel Multiple Unit (DMU), typically a mechanical transmission that uses gears is implemented. Locomotives are another matter, and the vast majority use an electrical transmission - the diesel engine itself drives a generator, that drives electric motors attached directly to each axle. Those that don't use electrical transmissions usually use some other, non-mechanical, system, such as a hydraulic system. 

Diesel engines were pretty much like this from the beginning, they were generally never incorporated any of the lessons learned from steam engine design.  They pack more power into a smaller space and are much lighter, in large part because of the differences in form factor. And while some efforts have been made to make steam engines that have that form factor, they haven't been very successful, in large part because they suffered virtually all of the disadvantages of a steam system and a diesel engine without retaining many positives of either design.

Internal combustion engines differ from steam engines in a large number of respects:

• With the exception of diesel, virtually all IC engines require a timed spark generation system, which in practice needs to be electrical.
• Each stroke of the engine starts with a high power, high intensity, explosion. To minimize stresses on the engine's cylinders, this needs to be converted to kinetic energy as quickly as possible. Diesel engines typically use a large number of cycles per second, using smaller cylinders than a steam engine, as a result of this.

Background

The first "railways" date back millennia. Initially little more than gooved tracks for wagon wheels, these evolved into plateways and finally modern railways as we know them today. Plateways involved horse drawn lines of carts, with flanged wheels on wooden or cast iron rails.

When the first steam locomotives appeared, largely in the early nineteenth century, that was the infrastructure, and the first locomotives wouldn't run on them. New railways were built, initially with cast iron rails, and then with wrought-iron when it became frighteningly obvious that cast iron was completely unsuitable. (When low cost methods to manufacture steel in bulk came along, rails were switched to steel for obvious reasons.)

Here you already see evidence of why certain decisions were made in the early evolution of steam. Cast iron was replaced with wrought iron. In the 1700s, cast iron was a cheap, easily obtained, metal for which mass production processes had already been developed. Cast iron is a carbon-rich iron alloy famous for its compressive strength and endurance but also infamous for how brittle it is. And wrought iron - well, wrought iron is as close as anyone could make to pure iron prior to the last hundred years or so, but was always extremely labor intensive to produce. Softer than cast iron, it was at least malleable. But it wasn't as strong as steel.

What about steel? Established methods for making steel in the 1700s and early 1800s were both energy and labor intensive. Melted wrought iron would be fused with carbon over a period of days of constant heat. It simply wasn't an option for early railway builders because steel was much, much, more expensive than either cast or wrought iron.

What about power? Portable power sources were plentiful in the early 19th Century, with solid fuels like wood and coal being by far the most common. Gases were rare, and oils existed but there was no serious industry to extract them - be that from the ground, or from plants - in massive quantities. Refining processes for oils extracted from the ground were very much in their infancy. Kerosene, the fuel that started the oil industry, didn't really start to be produced in high quantities until the mid 1800s. Fuels we know and "love" today like Gasoline and Diesel didn't come until much later.

And it's worth mentioning that electricity was more of a theoretical quantity than a practical technology in the early 1800s. The first practical battery, as we'd know it today, wasn't invented until 1836, and it wasn't portable.



Requirements of each engine


Steam engines consist of:

• A strong, high pressure, boiler, to make the steam
• A heat source for the boiler
• A valve/piston system to convert the pressure of the steam into movement
• A timing method to inject steam into the valve/piston system, and to allow it to be released
• A transmission method to convert the movement into rotational action upon the wheels

 For IC engines, we need:

• A fuel that can easily be inserted into the system as needed right to where it will be combusted
• A system to insert that fuel, with air, into the system when needed.
• A system to combust the fuel and air.
• Strong, high pressure, valves/pistons to contain the explosions, and convert each into movement
• A transmission method to convert the movement into rotational action
• A system of gears, or some other transmission method, to reduce the rotational action to a useful speed.

In practice, these systems require the following technologies:

Steam engines:

• Steam boilers require materials strong enough to contain a large amount of steam. In the 1700s/early 1800s, this in practice meant iron and cast iron. The systems weren't perfect, but they worked.
• Any heat source will do for heating the boiler, and so simply building a hot fire as needed would be all that was necessary. Coal quickly became the fuel of choice, as it was cheap and easy for a fireman to manage. In the 20th Century some very late steam locomotive designs used oil, largely because it made the process of managing the fire easier, but it wasn't necessary.
• The valve/piston system again needed to contain high pressures, and convert high amounts of energy into torque. In practice, we were talking about a largely solid box containing a piston, with valves operated by a system of control rods. Again, iron/cast iron were perfectly adequate for the job.
• A system of connected, pivoted, rods called a "valve gear", was attached to the near-edge of a driving wheel. As the wheel turned, it pushed the rods to and from the valves, ensuring they'd be opened and closed at the right times.
• The transmission for an engine of this kind needed to be simple, and extremely strong. In fact, with the design settled upon by locomotive designers, it needed high tensile and compression strength. A heavy, strong, rod was attached to the piston, which in turn was connected to a point on the near edge of a driving wheel. The other driving wheels were connected to one another with a horizontal bar that, likewise, was heavy and strong. As the piston rod moved in and out, it turned the attached driving wheel, which in turn drove the other wheels. Again, the iron technologies of the 1700s were more than up to the task of implementing this.

For diesel, things aren't quite as positive:

• Realistically, an automated process needs to inject fuel into the cylinders due to the large number of combustions per minute. This, in turn, makes it extremely difficult to use solid fuels. Liquid and gaseous fuels certainly existed in the 18th and early 19th Century, but they weren't cheap. They wouldn't have been on anyone's list of potential ways to drive something that required the enormous amounts of power a locomotive requires.
• Certainly had gas or oil been more cost effective in the time period, it wouldn't have been hard to create a method to inject fuel into the engine. No high pressures are required, just a pump and some method to time the injections, which could be connected to the output.
• However, actually exploding the fuel when needed might have been a problem. For most fuels, some form of reliable spark generator, one that doesn't exhaust itself after several hundred thousand cycles, would have been needed. The immature state of electrical technology pretty much rules out anything requiring a spark generator. For diesel, no spark is required, just compression, but diesel was not available until long after the oil boom.
• Steam got away with using regular and cast iron in the early days because while both suffer from fatigue, the number of stress cycles is relatively low for a steam engine. For an internal combustion engine, it's hard to imagine that this would be the case. Now, don't get me wrong - cast iron has been a component of engine blocks for many decades, but we're talking about considerably higher power requirements than that used by the average car engine. It seems improbable that the state of iron technology in the period would have produced a reliable, high MTBF, cylinder system.
• The transmission method for an IC engine tends to be similar, in some ways, to a steam engine's, except that there's more than one piston, and so each drives a rod (crankshaft) connected to a bar with kinks on it, that's made to rotate by having each rod connected to the kinks. Again though, this is something that would be rotating much more quickly than a steam engine's driving wheel, and so would be suffering greater stresses, again raising the question of whether the period's iron technologies were up to the task.
• Because of the speed of an IC engine's crankshaft, this can't be used to drive wheels directly. The available options are:
• Gears. But... again, huge stresses are involved. Remember I was saying earlier that almost all diesel locomotives use electrical transmissions, and those that don't use other weird systems like hydraulics? Well, that's because even today's materials don't lend themselves to making gears that require this kind of strength.
• Electrical transmissions - not available in the period in question.
• Hydraulics - it'd be interesting to know if anyone could have thought of this at the time, but you'd have had problems producing flexible materials capable of withstanding the high pressures involved.

A system of hacks

Earlier I described a 4-6-2 as being, in some ways, a kludge. What do I mean?

The 4-6-2 was usually built as an express locomotive, used for fast, non-stop, trains.
Let's start with the "6". The big driving wheels are a product of the fact that a steam engine generally drives the wheels directly. The speed of the engine is finitely linked to the speed you can inject steam, and expel it, from the valves. The power of the engine is going to be linked to the size of the valves, which will have a negative effect on this speed. And finally, just to add insult to injury, if you start adding more than two valves (one per side of the locomotive) as a way around these limitations, you'll start having serious problems with timings. (Lest anyone think this is theoretical, actual four-cylinder locomotives, using two sets of wheels per side, were made in the early 20th Century, and these engines suffered from severe wheel slip issues, amongst other things.)

So, given this, how do you increase the speed of the engine? Well, the obvious solution is simply to increase the size of the wheels, which is exactly what a steam engine does - it has great big wheels, so each piston movement translates into a larger amount of movement.

The problem you get at this point is that big wheels have two problems. The first is that they're more prone to slip, and second their size makes them somewhat more difficult to turn curves, to the point that they're very likely to derail.

For the first, you have six wheels, rather than two. The issue with the locomotive following curves however required a little more work.

So our next hack involves the "4-" - the truck at the front. This has small wheels, that hug the track, pulling the locomotive in the right direction. The driving wheels thus need to make contact with the track, but they can have much more liberal flanges, allowing them to slide left and right without there being any risk of them leaving the track altogether.


Finally, the 4-6-2 needed a fairly large boiler to provide enough power to drive the engine at speed. With vertical space at a premium (and likewise width - think tunnels) the one solution to this is to make the engine longer. However, a long, heavy, boiler needs to be supported, and the two wheels at the back are for that.


Conclusion

So that's it. You probably knew all that anyway, I just enjoyed writing it down and figuring out the thought process.