Term Paper: From Aeolipile to Locomotive

[Romulus Augustulus]

I'd like to see giant steam powered siege towers...with cannons, and archers...and all sorts of stuff along those lines. Imagine a steam powered Helepolis! FYI, Helepolis was a giant siege tower which was used in a failed invasion of Rhodes...the same one that caused the inhabitants to build the Colossus. Helepolis was broken down and went into the production of the Colossus.

 

[carlton_bach]

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?

It is likely that mineral coal was used to some extent at a very early age, and continued in use through the Roman era. However, this was likely not mined as much as collected. At the time, its usefulness was strictly limited (you can't use mineral coal in a forge or furnace without coking, and while it burns, it doesn't burn clean or pleasantly), and in roman times the forests were still sufficient to supply all the charcoal and firewood needed through the parts of Europe that had mineral coal deposits close to the surface.

Now, if some clever-dick Roman figures out coking...

 

[DominusNovus]

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?

According to the Pennsylvania Coal Mine History, "the very first coal mined that is recorded was coal that was mined during the Roman Occupation of Britain in 55 BC to 436 AD along the banks of the rivers Clyde and Forth."

 

[Bill Cameron]

Absurd! That Heron could develop a windmill!

DN,

I didn't say it was absurd at all. Remember to vet your sources. Does Heron's unadulterated text actually mention windmills? Or did some helpful Middle Ages monk insert a picture of one while copying the text?

Ok. Maybe he could.

Of course he could and, unlike steam engines, each and every part required to make one was already available.

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.

Yup, he made toys and not tools.


Bill

 

[DominusNovus]

I didn't say it was absurd at all. Remember to vet your sources. Does Heron's unadulterated text actually mention windmills? Or did some helpful Middle Ages monk insert a picture of one while copying the text?

I was kidding about it being absurd. Its my sense of humor.

The text I have seems to mention it, but I'd hardly call it unadulterated.

I'm thinking of doing the paper just on how Heron's ideas could be applied, so windmills and steam engines would both be included.

 

[DominusNovus]

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

Hmmmm...

It occurs to me...

A) these rams will be somewhat valuable, due to their engines
B) Rome won't want to just waste them in kamikaze attacks
C) therefore, they ought to have some armor
D) this increases the demand for iron (assuming, of course, they use iron for the armor)
E) this increases the demand for cheap iron
F) necessity being the mother invention, somebody figures out coking, increasing the utility of coal
G) this, of course, increases the demand for coal
H) so we get people mining more coal, and wanting pumps for the coal

hmmm?

Here's a question. We often talk about how close Song China was to industrializing. Well, why were they using coal so much more than Rome? What where the differences?

 

[carlton_bach]

Hmmmm...

It occurs to me...

A) these rams will be somewhat valuable, due to their engines
B) Rome won't want to just waste them in kamikaze attacks
C) therefore, they ought to have some armor
D) this increases the demand for iron (assuming, of course, they use iron for the armor)

I'm not sure they could get the kind of speed and mass that would be required for effective shipkillers. But if they could - the Roman armored their fighting ships with bronze (when they did). That might still give you demand for coke, but not for cast iron, and the inherent rarity of the material is another headache..

hmmm?

Here's a question. We often talk about how close Song China was to industrializing. Well, why were they using coal so much more than Rome? What where the differences?

1000 years of history, less available other fuel (for most of its early history, Europe was a continent full of stuff, not people), and cast iron. Many iron ore deposits in China are of a different composition to those in Europe, with a significantly lower melting point.

 

[DominusNovus]

I'm not sure they could get the kind of speed and mass that would be required for effective shipkillers.

Well, I guess I'll have to look into the engineering of this a bit more.

That might still give you demand for coke, but not for cast iron, and the inherent rarity of the material is another headache..

inherent rarity of coal, I assume?

1000 years of history, less available other fuel (for most of its early history, Europe was a continent full of stuff, not people), and cast iron. Many iron ore deposits in China are of a different composition to those in Europe, with a significantly lower melting point.

hmmmm...

There's an interesting paradox for ya. Europe has too much stuff, and not enough people, yet the common reason we say they didn't have an industrial revolution was that it was a slave driven economy...



Ok, any thoughts one what other applications Heron's inventions could be used for?

Anything simple and steam operated is a given, what can we do with that?
Some sort of steam powered weapon? Using the pressure to fire a projectile?

Windmills, obviously, given that he may or may not have had one for an music organ.

What else? I think our best options are military ones, since thats one area where manpower was always an issue.

 

[DominusNovus]

Another thought, as suggested by Faellin. Have the Romans invent the printing press, enabling Heron's ideas to be widespread and developed more easily.

The printing press is relatiely easy, but paper, extremely helpful, but not crucial, to a printing press, isn't. What was that battle between the Arabs and the Chinese, where the Arabs managed to capture a bunch of Chinese papermakers? Any idea if such papermakers would be in an expeditionary force led by one Ban Chao, say, around AD 98? Say Gan Ying gets to Rome, something goes wrong, and Ban Chao ends up in battle with some Roman Legions under the command of the new emperor, Trajan. So far from his support structure, Ban Chao is defeated, and Trajan takes some papermakers captive.

A stretch, isn't it?

I'm worried I'm going to have to fall back on windmills...

sigh.

 

[carlton_bach]

inherent rarity of coal, I assume?

Bronze. Iron is as common as dirt (literally), but bronze components are both rarer and less widespread geographically. Easier to mine and refine, though.

There's an interesting paradox for ya. Europe has too much stuff, and not enough people, yet the common reason we say they didn't have an industrial revolution was that it was a slave driven economy...

I don't buy the slave economy story. That's strictly a 'whig history feelgood' party line. Yes, slavery had something to do with it, but the Caribbean colonies of the 17th and 18th centuries had more, cheaper slaves under worse conditions than the ancient world, and they were very happy with technology. OTOH Roman Gaul, despite slaves being fairly rare, was not exactly a hotbed of high tech. There are aspects to the ancient mindset that make technology a difficult concept, but it is far more complex than 'slaves or machines, not both'.

If you are looking for a 'lots of people, little stuff' economy, go to Roman Egypt or Syria - incidentally, the places where technology advanced much farther. Think on it: we have evidence for the odd watermill and the occasional other 'advance' (stern rudder, wheeled plough, harvester) from Roman Western Europe, and this is the result of practically digging up the entire place. In Syria and Egypt, Roman sites have barely been touched and we already found stuff that engineers still have a hard time explaining cogently.

 

[Romulus Augustulus]

The battle in question was the Battle of the Talas River, which occured in 751 CE near the site of modern day Tashkent. This halted the westward expansion of the Tang Empire, and, since it touched off An Lushan's Revolt, led to its eventual decline. The Arab Abbasid Caliphate, which won the battle, managed to stop the Tang's westward expansion and brought back the secret of paper making.

 

[DominusNovus]

The battle in question was the Battle of the Talas River, which occured in 751 CE near the site of modern day Tashkent. This halted the westward expansion of the Tang Empire, and, since it touched off An Lushan's Revolt, led to its eventual decline. The Arab Abbasid Caliphate, which won the battle, managed to stop the Tang's westward expansion and brought back the secret of paper making.

I know all that, just forgot the name.

 

[DominusNovus]

I don't buy the slave economy story. That's strictly a 'whig history feelgood' party line. Yes, slavery had something to do with it, but the Caribbean colonies of the 17th and 18th centuries had more, cheaper slaves under worse conditions than the ancient world, and they were very happy with technology. OTOH Roman Gaul, despite slaves being fairly rare, was not exactly a hotbed of high tech. There are aspects to the ancient mindset that make technology a difficult concept, but it is far more complex than 'slaves or machines, not both'.

I agree with you there. I once read a paper on the roman economy that convinced me that the slave economy was not the main reason for lack of technological development.

If you are looking for a 'lots of people, little stuff' economy, go to Roman Egypt or Syria - incidentally, the places where technology advanced much farther. Think on it: we have evidence for the odd watermill and the occasional other 'advance' (stern rudder, wheeled plough, harvester) from Roman Western Europe, and this is the result of practically digging up the entire place. In Syria and Egypt, Roman sites have barely been touched and we already found stuff that engineers still have a hard time explaining cogently.

Could you elaborate on this stuff from syria and egypt?

 

[DominusNovus]

Well, evidently, Heron knew of pistons and precision tight enough to make a workable syringe.

Agh! One more piece of the puzzle that the guy had, and he still didn't figure it out.

 

[DominusNovus]

Engineering in the Ancient World, by JG Landells

I'm absorbing it right now, and it covers almost all the problems with Heron's steam engine. However, in his discussion of the force pumps described by Heron and Vitrivius, as well as others found in archeological digs (including a wooden 8 cylinder pump found in Brittany), the construction of these devices seems quite advanced. Add to this that his wind organ was basically a force pump (for air) attatched to a windmill.

So, the idea of converting rotational force to the force in a piston was there. Since overshot waterwheels were quite possibly inspired by bucket wheels used to raise water (basicly, the exact opposite task, using the force of falling water on a wheel as opposed to applying force on a wheel to raise water), its not unreasonable to use the same idea here (reversing the design of an existing mechanism). Convert the force in a piston to rotational force. Basically (and this is a very crude description), take the fire engine, attatch it to the wind organ, replace the windmill with a paddlewheel, add a boiler to the whole mix, and put the whole thing on a galley. Bada bing, Roman steamship.

Sure, it wouldn't be perfect. But, the Romans were good at refining Greek ideas, especially ones with military potential.

 

[Romulus Augustulus]

They had evidence of coal use at Dolni Vestonice...

 

[DominusNovus]

They had evidence of coal use at Dolni Vestonice...

The Romans certainly knew of coal, and used it to some degree. Just not enough to warrant mining it.

Besides, I'm afraid that, had they started to mine it, they might use their rotary pumps, such as those in other mines. A series of bucket wheels, raising the water higher and higher.

 

[DominusNovus]

I spent so much time typing this for SHWI, I might as well post it here too.

Ok, so it a glorified bump. Whoopie.

Ok, after reading up on Engineering in the Ancient World, by JG
Landels, I'm convinced that Heron of Alexandria (or someone shortly
after him) could have invented a workable steam engine during the Roman
Empire.

If I may, I'll divide the engine into 4 parts, a boiler, the pistons, a
condensor, and an output device.

1) The boiler's easy, just scale up the boiler from the aeolipile or
any of his other devices.

2) The pistons aren't quite as easy, but there were plenty of examples,
including some in Heron's own Pneumatica (the fire engine and syringe,
for example). An impressively complex example, the Valverde Huelva
Pump, was found in Spain. Four pumps were found in a shipwreck dating
from the 1st century AD. Tests suggest a 95% capacity. Also
noteworthy is an 8 cylinder force pump found in Brittany.

Heron evidently had much experience with such pumps, mainly those in
use for fire engines. Vitruvius seems to describe pumps made through a
'lapping' technique, whereby the piston is first tooled in a lathe,
then rammed down the cylinder until it fits right. Vitruvius also
comments on air pumps (for organs), suggesting wrapping the piston "in
sheep's hide with the woold still on it."

Clearly, the Romans and Greeks had an extensive knowledge of pumps and
pressures and how to get them to work, even for gases. If an air pump
could be built, surely a steam pump could be as well. The biggest
challenge would be would be creating a single action piston (or, if
were were to be ambitious, a double action piston). Its a jump,
admittedly, but its not too far a jump.

3) The condensor is probably the biggest stretch of them. Simply
because, as far as I currently know, there's nothing contemporary like
it. Even then, you don't absolutely need it, if you're near a source
of fresh water. But, its handy, and pretty simple. Just run the
exhaust steam pipes through a tank of water. Pretty simple.

4) The output device will be, for this example, a paddlewheel for a
steamship, as ship propulsion was one area that was simultaneously:
labor intensive
done by free men
valuable to the military
Now, we have to convert the force of a piston to a wheel. Seems simple
to us, but would it be simple for Heron and his contemporaries?

Suprisingly, it probably would be fairly simple. If we look at Heron's
wind powered organ, the setup is basicly a windmill (the only example
of such a device in antiquity, in itself a good starting point for AH)
used to force a piston up and then release it down (radial rods on the
mill, which would catch a lever attactched to the piston, pull the
lever down, forcing the piston up, before slipping past the lever,
allowing it to rise and the piston to fall) pumping air into the organ.

Basicly the problem now is to:
reverse the design (of course replacing the wind mill with a
paddlewheel)
develop a better method of converting the work besides that "catch and
release" system.

Reversing the design is pretty simple. In fact, that is quite possibly
exactly how overshot waterwheels (known in that time) were likely
developed. Bucket wheels, where a wheel was turned in water in order
to scoop the water up and raise it to a height. In other words, apply
power to a wheel and get water to the top. It is likely that some
bright guy simply decided to put water at the top, and get power out of
it. Simply reverse the process. Bada bing, literal reverse
engineering. So, its not hard to imagine that someone looking at a
wheel powering a pump, could think of a pump powering a wheel.

Oh, and the Romans knew of paddlewheel boats. Somebody even had an
idea of an ox powered paddlewheel boat. It likely wouldn't have
worked, but the fact remains that the general idea was there.

Now, as for replacing the trip mechanism, its a small hop, but I think
its doable.

So, there you go. Put it on a galley, and you've got a Heronic
steamship.

What do you guys think?

 

[NHBL]

Plague?

IF you assume that the slave economy hampered the transition from toy to tool, then perhaps your POD could be a plague of some sort. Since the lower classes live in poorer conditions, casualties will be higher among them. Instant rise in the cost of labor...
NOW someone can see one of these toys and think of a way to make some money with it...

 

[LordKalvan]

IF you assume that the slave economy hampered the transition from toy to tool, then perhaps your POD could be a plague of some sort. Since the lower classes live in poorer conditions, casualties will be higher among them. Instant rise in the cost of labor...
NOW someone can see one of these toys and think of a way to make some money with it...

This is a good idea, something similar to the Black Death in Europe, and with similar results in terms of social mobility and labor costs