The delay in steampower generation

[gagenater]

About motivation for the developement: I think at least ancient military might be tempted to use steam power for the propulsion of their navy. It seemed to be an important issue...

Steam engines were to large, innefficient and dangerous to be used on a ship for ~ 100 years after their invention. Also until the development of large coal fields finding enough fuel to run them was a considerable problem that restricted them to short trips only. (except in early America where they were simultaniously clear cutting a continent and could run them on wood)

 

[JodelDiplom]

Let's turn this around: what if those British mines weren't that deep and the urgency to innovate a steam engine there at that time doesn't materialise. Where and when would the next attempt be at - Germany, France, Sweden, Belgium?

Depends. A number of states had the necessary ingredients (stability, investment capital, coal mines) in place around the turn of the 19th century. Prussia, Belgium, France, just to name the perhaps most obvious ones. The laws of thermodynamics were pioneered by the young French scientists around the turn of the century (Carnot and others - although of course they built on the practical results of Watt etc) so it stands to reason they had the brainpower and money to invent machines.

 

[Ming]

I'd think primarily advances in steel generation right? Iron seems like it wouldn't work nearly as well for the sort of pressures that a good steam generator would need.

Early steam engines used Iron, and the ancient world could get away with heavy bronze steam devices, which would be nearly as strong. These devices would be expensive and heavy (you can forget about it propelling itself), but possible.

The are other practical problems in keeping back ancient or medieval steam technology such as efficient gearing and accounting for the expansion of heated components, but a big one is the lack of precision in construction. These devices will leak so much water and heat, consume so much fuel and be so less efficient than man, animal, or alternate power sources that no one would bother with the things. You might end up needing just as much if not more labor to keep the things running as you would employ in directly powering whatever you intended to use the engine for.

That said, there are some medieval developments that could benefit steam technology that were used in non steam devices (like reciprocating pistons) but you can't get away from the infefficiency problem until near historical times. Someone else mentioned lack of infrastructure in the ancient world and the diminished ability of those societies to move large amounts of fuel (and possibly water) would limit the usefulness of steam engines as well.

 

[pithorr]

Why would they?
There are galley slaves aplenty and those don't be pose a firehazard.

They use to become tired after a half an hour of intense rowing.

 

[trybald]

They use to become tired after a half an hour of intense rowing.

Then you replace them with a second shift.

 

[gagenater]

Then you replace them with a second shift.

And when they get tired you pull to shore, drink a glass of wine and take a nap.

Early steam powered ships had poor endurance too. The steam engines were so in efficient that it was difficult to carry enough fuel to keep them running for long. This was workable for a ferry or a tug that regularly went to land , but not for a ship expected to cover any reasonable distance. The rowers will recover with a little time and some food. The steam engine needs fuel and that's harder to come by.

 

[pithorr]

When you are in the middle of fight for many hours there is often no time to change a shift or recover... Vessels with the independent propulsion could have some advantage then.

Well, I meant what could be the reason in thinking that would cause the boost for the invention of a steam engine in the acient era. Of course, in the beginning such propulsion wouldn't be so much effective, but consequently improved it could start to work, as it happened later. Such idea was not abandoned in the 19th century despite many flaws, wasn't it?

 

[TheDanish]

It largely boils down to inefficiency (the first steam engines were 99% inefficient), and the fact that human beings were the most efficient energy converters until the steam engine was improved in the nineteenth century. See: McNeill, Something New Under the Sun.

 

[k-59]

Still sort of surprising that they weren't even widely used on prestige projects IMO. The mere spectacle of work being done seemingly by magic... I remain surprised it was so widely ignored.

Sir! We have this stack of money to spend on the project. Would you like to:
A] Build a solid gold statue of yourself.
B] Developed a new technology that may someday speed construction.

 

[CatKnight]

Further, imagine how much an early steam engine would weigh coupled with how much room it would take up. Now toss in all its fuel. These ships were cramped to begin with.

Also, while the ancients could probably have figured a propeller out (combine Archimedes with known rowing techniques), attaching that to a steam engine ... my gut says that would have been an issue for them.

 

[Ming]

Also, while the ancients could probably have figured a propeller out (combine Archimedes with known rowing techniques), attaching that to a steam engine ... my gut says that would have been an issue for them.

Interesting question. Could you make some sort of manual propeller drive (say an archimedes screw powered by muscle) that would be useful on ships?

Obviously, the transfer of mechanical energy would be inefficient but maybe you could get something out of milling technology, where say an animal team turns a screw and it isn't very fast but at least you don't need galley slaves? (and horses/mules have much more endurance and weigth to power ratio than humans)

 

[NapoleonComple]

I would've thought trains would appeal to the Roman Empire. Imagine sword-and-shield armed legionaries being ferried about on steam-powered rails only to be ambushed by Germanic raiders on horseback, train-robber style.

...I should probably have saved that idea for a book.

 

[Xeorm]

Interesting question. Could you make some sort of manual propeller drive (say an archimedes screw powered by muscle) that would be useful on ships?

Obviously, the transfer of mechanical energy would be inefficient but maybe you could get something out of milling technology, where say an animal team turns a screw and it isn't very fast but at least you don't need galley slaves? (and horses/mules have much more endurance and weigth to power ratio than humans)

I'd bet you could make a ship propelled by such a thing. But why would you want to?

Getting the animals to do the proper motions likely means you need space for them to walk/run, and that's iffy. Animals are also notoriously unreliable in combat conditions and in getting them to do what you want, so It'd be difficult to get any sort of improvement over regular galley slaves.

Plus, galley slaves are dirt cheap, so it's not like you're making any sort of profit by using animal-powered combat ships.

 

[StephenT]

*ahem*

Greek and Roman galleys in ancient times were not rowed by slaves. An oarsman was a skilled professional, who expected to be well-paid for his labour. They were usually armed for self-defence.

The galley slave was a late mediaeval development - you can blame France, Genoa, Venice, the Ottomans and the Barbary Corsairs for that, not Athens or Rome.


Now: that said, please continue with the discussion on steam engines.

 

[Ming]

I'd bet you could make a ship propelled by such a thing. But why would you want to?

Getting the animals to do the proper motions likely means you need space for them to walk/run, and that's iffy. Animals are also notoriously unreliable in combat conditions and in getting them to do what you want, so It'd be difficult to get any sort of improvement over regular galley slaves.

Plus, galley slaves are dirt cheap, so it's not like you're making any sort of profit by using animal-powered combat ships.

Perhaps not for combat. (In fact I imagine, rough seas would probably be enough to drive most animals wild without extensive breaking and training which would erode any cost savings.) I was thinking there may be some calm water use case like a medium distance ferry where the animals might make sense.

Although for such a use case, the drive would probably be more of a hassle than relying on wind.

*ahem*

Greek and Roman galleys in ancient times were not rowed by slaves. An oarsman was a skilled professional, who expected to be well-paid for his labour. They were usually armed for self-defence.

The galley slave was a late mediaeval development - you can blame France, Genoa, Venice, the Ottomans and the Barbary Corsairs for that, not Athens or Rome.


Now: that said, please continue with the discussion on steam engines.

What? Ben Hur lied!

What changed and made slaves more economical than paid labor at this time?

 

[gagenater]

Perhaps not for combat. (In fact I imagine, rough seas would probably be enough to drive most animals wild without extensive breaking and training which would erode any cost savings.) I was thinking there may be some calm water use case like a medium distance ferry where the animals might make sense.

Although for such a use case, the drive would probably be more of a hassle than relying on wind.

Animal power was used for ferries in calm water on rivers and canals, but the animals weren't on the boat/ship - instead a path along the waters edge was made a 'towpath' and a rope was run from the animals to the boat and they pulled it from the land. This way you don't need to worry about the hassle, space and problems of actually putting the animals on the boat, or coming up with some mechanism to transfer the animal's pulling power into motive power for the boat.

 

[pithorr]

What? Ben Hur lied!

What changed and made slaves more economical than paid labor at this time?

I think it applies to combat triremes. Slaves were not trusty enough for them, but might be used in merchant ships.

 

[StephenT]

Most merchant ships in classical times weren't rowed. Why spend a fortune on food and drink for hundreds of rowers, when the wind is free?

As for what changed, mostly the Black Death. After that, labour was scarce and expensive compared to before 1350, and states could no longer afford to pay huge numbers of oarsmen. They started using convicts and prisoners of war for the job. Venice was one of the last to turn to slave labour - until the early 16th century they still used free men (although they did have conscription in wartime).

There was also a technological change. Instead of the old system of having multiple banks of oars, it became normal in Renaissance galleys to have just a single bank of much larger oars pulled by three, four or five men each. That required much less skill (to stop the different oars hitting each other) and just needed brute force; so it was more suited for slave labour. But whether this change happened because of the introduction of slavery or vice-versa, I'm not sure.

 

[Ming]

Most merchant ships in classical times weren't rowed. Why spend a fortune on food and drink for hundreds of rowers, when the wind is free?

In that case, what did these highly trained Oarsmen do when there wasn't a war?

 

[pithorr]

In that case, what did these highly trained Oarsmen do when there wasn't a war?

Enjoyed their life in the Mediterranean coast
I think the same what hoplites did in the peace time - run their farms and shops.