Term Paper: From Aeolipile to Locomotive

So, I serendipitously ended up in a class on technological development. 40% of the grade is based on a report on one of three choices:
a) a past technology
b) an alternative to a past technology
c) a future technology

Take a stab at which I'm going to choose.

(though the future one would interesting, too)

Anyway, as you might have guessed, I'm planning on doing my paper on Heron and his aeolipile, and how to make the jump from it to a true steam engine (unless you guys have an utterly irresitable alternative). So, I ask you guys what you think of this idea, if you know any good sources, what problems you see with this idea (not the paper, but the actual progress), etc. I don't think I'd be able to have Heron himself devise a true steam engine, how long do you guys think it would take for someone to develop one?

A long, long time. The Greeks were pretty short on the necessary fuel, and the science required to build one.

How about something on Fulton's steamships, or explosive shells?

Faeelin said:

How about something on Fulton's steamships, or explosive shells?

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You know, my paper could be about why the technical limitations on an early true steam engine were prohibitive. That fulfills the requirments just as well.

DominusNovus said:

You know, my paper could be about why the technical limitations on an early true steam engine were prohibitive. That fulfills the requirments just as well.

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But not near as fun...

Something to check into

My understanding of early steam is not extensive, but perhaps I can offer an avenue to investigate.

A steam engine needs truely round holes, and excellent precision on many parts, or it will loose lots of steam through poorly fitting parts. As I understand it, these precise holes aren't easy to make, nor are perfectly round pistons. I suspect that, if you can deal with these difficulites, you could get some sort of useful steam engine, given time to experiment.

More important, you need them motivated to build a steam engine.

DominusNovus said:

You know, my paper could be about why the technical limitations on an early true steam engine were prohibitive. That fulfills the requirments just as well.

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DN,

Leaving aside the metallurgical issues; iron production, casting, etc., and the social issues; why an engine when you have slaves?, it is a very big intellectual step from a reaction jet to a piston. Were piston pumps even around in the Classical Era?

A scaled up aeolipile would work very poorly as a 'steam engine'. Sure, the pivot shaft could drive gears or belts, but the amount of work produced would depend on a whole host of factors - the size of the nozzles, the distance they are separated from each other, what sort of bearings are being used, etc. Some of that could be determined by trial and error, alot of trial and error.

Then you'd have to tackle the problem of continaully feeding the aeolipile water. Without condensers, steam engines use more water than fuel. Without a hollow pivot shaft acting as a feed water conduit, the aeolipile would need to be stopped, refilled, and then started again. That's hardly a useful machine.

So, you'll have technical issues, social issues, and - most of all - a big theorectical issue - reaction jet to piston - to tackle before Heron builds a locomotive.


Bill

Piston pumps were around. Pneumatics were around. The connection wasn't made though. Partly because the required manufacturing tolerances were incredibly labour-intensive, partly because of no perceived need, but above all I think because the information didn't disseminate quickly and broadly enough.

carlton_bach said:

Piston pumps were around. Pneumatics were around. The connection wasn't made though. Partly because the required manufacturing tolerances were incredibly labour-intensive, partly because of no perceived need, but above all I think because the information didn't disseminate quickly and broadly enough.

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Maybe most of all because there was no perceived use for a LOUSY steam engine.

Remember that the first form of steam engine put to practical use was the Newcomen engine. IIRC, it actually used (very) partial vacuum from condensing steam, rather than steam pressure, it was wretchedly inefficient, and too bulky to be used in a vehicle. It was also wretchedly inefficient, only recovering something like 1 percent of the energy in its fuel.

But the Newcomen engines were used to pump out coal mines, meaning that coal was plentiful, and it was cheaper to use some of it to power the engines than use human or animal power.

The point here is that this was a specialized application for which the Newcomen engine was suitable - and once it was in use, there was an interest in improving it, leading to the Watt engine, which turned out to be versatile.

The Greeks didn't mine coal, so they would have had no use for the Newcomen engine, and no opportunity to crawl before walking. They'd have had to go straight from the aeolipile to the fairly demanding Watt engine.

-- Rick --

Rick Robinson said:

The Greeks didn't mine coal, so they would have had no use for the Newcomen engine, and no opportunity to crawl before walking. They'd have had to go straight from the aeolipile to the fairly demanding Watt engine.

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By the time we get to Heron, we're not talking about the Greeks, but the Romans.

New question. Were pumps needed at all for other types of mines (iron, tin, etc.)?

Next. What would be some good ways to increase the use of coal in the Roman Empire?

What about the effects of an early introduction of the heavy wheeled plow and other medieval-era tools and techniques? Earlier adoption of such technology in Europe could have profound effects on its development...

Romulus Augustulus said:

What about the effects of an early introduction of the heavy wheeled plow and other medieval-era tools and techniques? Earlier adoption of such technology in Europe could have profound effects on its development...

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Yes, but not nearly as sexy.

carlton_bach said:

Piston pumps were around.

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Carlton,

I know there were 'siphons'; big syringe-type 'squirt guns', but were there back and forth piston pumps with check valves, bushings, and all the works?

Pneumatics were around.

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Yeah, the singing statues and all that stuff.

The connection wasn't made though. Partly because the required manufacturing tolerances were incredibly labour-intensive, partly because of no perceived need, but above all I think because the information didn't disseminate quickly and broadly enough.

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I also think because the devices were perceived as toys and not tools. They had temple doors opening hydraulically. They had holy water dispensed by a coin operating machine. They had those singing statues. They had whatever that mess of gears fished out of the Aegean was. They had a steam propelled bird. They had lots of one-of-a-kind gadgets, but they never saw them as useful tools. All those things were just nifty toys.


Bill

DN,

I think you should toss out Heron's whirligig and write about windmills instead.

You can see now just how high the 'barriers to entry' are for a steam engine in the Classical Era. The metallurgy wasn't available, the idea of reciprocating pistons may not have been available, the intellectual leap from 'toy' to 'tool' was definitely not available. Other than resorting to special pleading or ASBs plopping a genius into the mix, no useful steam engine will be developed during this period.

Look at how we developed the steam engine, it was a near run thing. The Newcomen engine was absolutely wretched. It could have been used no where other than a coal mine and for nothing other than pumping water. The only thing that made it's use worthwhile was that the facility using it also produced the fuel it used. Because there was a local abundance of coal and a local scarcity of labor, the horridly inefficient Newcomen engine got it's chance. It still took decades for Watt to make his improvements and even more decades for steam engines to be seen as useful in jobs beyond pumping water out of mines. If not for the need to pump water out of coal mines, steam engines may have been delayed until a much more efficient variety was put together by another tinkerer.

Contrast all that to windmills. It's still mindboggling that windmills didn't appear on the scene until the 9th or 10th century in Iran. The wheel had been in use for millenia and sails for ships almost as long. Why someone never thought of combining the two is a head scratcher. I mean, windmills seem like such a no brainer! And they seemed like a no brainer to the people of the time too! Within a century of their being developed, they went from horizontal(1) to vertical and spread all over Europe and the Mediterranean littoral. William's Domesday Book lists quite a number of them.

Heron and company can make windmills. They can already make sails. They can malready ake lattice work. They can already build towers out of wood or stone. They already have grinding stones driven by slaves, waterwheels, or draft animals. They already have irrigating 'bucket wheels' driven by slaves, waterflow, or draft animals. All the parts are there. All the jobs are ones that need doing. All the hints are there. Nothing new need be developed. All you need is someone to put the bits together.


Bill

1 - The first variety of windmill resembled a paddlewheel lying on it's side. The region of Iran where they came about has a season where the wind blows primarily in one direction. These first windmills were set up behind walls with just a little bit 'peeking' out for the wind to catch.

Could the Romans have developed steam powered weapons?

Think of a tube, through which a jet of high pressure steam is flowing. Now put a slit on top and on top of that a hopper filled with arrows, each having a circular washer around the shaft exactly the tubes diameter. The arrows fall through the slit, and as fast as they do, are pushed out the tube end at high velocity. A steam powered machine gun. This requires a fairly high degree of accuracy overall but its a weapon and if anything motivated the Romans....

Or is that even possible?

As a completely difffernt possibility. How about if the soldier who killed him had obeyed orders and brought Archimedes to his commander alive?

Bill Cameron said:

Carlton,

I know there were 'siphons'; big syringe-type 'squirt guns', but were there back and forth piston pumps with check valves, bushings, and all the works?

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Yes. Valves and parts of a bronze (well, 'copper alloy') pump were found in italy and a reconstructed version could create a continuous stream at quite a presure. It was assumed that the machine was powered by four men and used for firefighting, but that's just guesswork. Continuous-stream pumps were also used on deep wells, in which case they were usually made from wood and only survive in bog finds (we have two).

Yeah, the singing statues and all that stuff.

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Actually, high-pressure pneumatic pistons could be built and were understood far enough to prompt the design (and possibly protoype) of a pneumatic catapult. The design was tried out by German archeologists and they found a) it was feasible with the technology of the day and b) it works. Unfortunately, it has few advantages over traditional designs and massive disadvantages (higher cost, difficult manufacture, maintenance and repairs).

I also think because the devices were perceived as toys and not tools. They had temple doors opening hydraulically. They had holy water dispensed by a coin operating machine. They had those singing statues. They had whatever that mess of gears fished out of the Aegean was. They had a steam propelled bird. They had lots of one-of-a-kind gadgets, but they never saw them as useful tools. All those things were just nifty toys.

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Well, they also had pumps, pressure-bearing weaterpipes inside houses, showers, screw thread mechanisms and other very much utilitarian stuff. The main problem really seems to be that it doesn't 'click' - nobody expands the application. I'm guessing it's mostly an information culture problem.

wasnt the spainsh king in the 1500s (maybe charles) shown a ship that was powered by a steam engine. Its not as early as Hero, byt steamships that early would have huge effects.

carlton_bach said:

I'm guessing it's mostly an information culture problem.

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I would agree. The big jump in European technology occurred after the introduction of the printing press, which allowed scientific discoveries to be widely disseminated and cross-pollenization of ideas to occur. In the ancient world, scientists in far-flung regions worked in relative isolation from each other and as a result did not usually have the opportunity to build on each other's ideas.

Bill Cameron said:

Heron and company can make windmills. They can already make sails. They can malready ake lattice work. They can already build towers out of wood or stone. They already have grinding stones driven by slaves, waterwheels, or draft animals. They already have irrigating 'bucket wheels' driven by slaves, waterflow, or draft animals. All the parts are there. All the jobs are ones that need doing. All the hints are there. Nothing new need be developed. All you need is someone to put the bits together.

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Absurd! That Heron could develop a windmill!

Ok. Maybe he could.

You know, I think the greatest tragedy of Heron is that most of his inventions were made for temples and theaters, and not the major engineering body of the day, the Roman army.

Hey, a thought just popped into my head. Anyone ever heard of those toy 'pop pop' steam pulse boats? Really really simple steam engine there. Just a boiler and some pipes, nothing fancy. Anyone know if they scale up well?

DominusNovus said:

Absurd! That Heron could develop a windmill!

Ok. Maybe he could.

You know, I think the greatest tragedy of Heron is that most of his inventions were made for temples and theaters, and not the major engineering body of the day, the Roman army.

Hey, a thought just popped into my head. Anyone ever heard of those toy 'pop pop' steam pulse boats? Really really simple steam engine there. Just a boiler and some pipes, nothing fancy. Anyone know if they scale up well?

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Fairly well; IIRC, they're used in races down south.

Unfortunately you can only build small boats. Maybe some killer rams, but little else.

Rick Robinson said:

The Greeks didn't mine coal, so they would have had no use for the Newcomen engine, and no opportunity to crawl before walking. They'd have had to go straight from the aeolipile to the fairly demanding Watt engine.

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DominusNovus said:

By the time we get to Heron, we're not talking about the Greeks, but the Romans.

Next. What would be some good ways to increase the use of coal in the Roman Empire?

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According to Wikipedia, coal was not mined until the Middle Ages. Does anybody here know if this is correct, or did the Romans mine it?