Hacker News Reader

Comment by wil421 | Hacker News Reader

They didn’t have the metallurgy to make a reliable steam engine. However I think they could’ve industrialized a lot of things using a bronze turbine or waterwheel and a ton of belt systems like old factories once did with line shafts.[1]

[1]https://en.m.wikipedia.org/wiki/Line_shaft

View on HN

Not only they didn't have the metallurgy, the British didn't have it in 1712, when the Newcomen engine was invented. Some brave souls tried to create engines with steam under pressure, but ended up blowing up things. So, for almost one hundred years, the steam engine worked on negative pressure. The work was not done by the steam, but rather by the atmosphere when the steam condensed and created a vacuum. James Watt's big innovation was not to allow somehow for more pressure in a cylinder, but to improve the condensation of the steam.

So, what was missing in the early Roman empire was not the metallurgy, but the understanding that air has weight, and it's a considerable amount of weight, which can be harnessed to perform work. To us that insight seems trivial, but if you think about it, it could not have come before the scientific method was developed. The Magdeburg experiment [1] that showed that a team of horses cannot separate two hemispheres kept together by the weight of the atmosphere was not only truly brilliant, but it depended fundamentally on a culture of experimentation, culture that simply did not exist on thousand years before.

[1] https://en.wikipedia.org/wiki/Magdeburg_hemispheres

> didn’t have the metallurgy

I wonder if in theory they could've made in bronze. It was still generally the superior metal compared to iron/steel in most ways till the middle ages (IIRC) and much easier to work. It's only downside was cost.

If you make both piston and cylinder out of bronze, they stick together and wear quickly. It's better to make one from bronze and one from iron.

And not much motive to develop it. Slaves were abundant and the practice was widely accepted in paganism. This skewed the economics to favor making use of them.

Slaves were cheaper than the early steam engines. As such even if you built a steam engine (I think historians have documented primitive ones that did work - but they were small, very low power, and inefficient) it wasn't clear that the effort to develop it into something better is worth the cost.

The acoup blog went into detail on this topic [0]. Central idea was that early steam power was so inefficient the only way it was worthwhile was for use in coal mines where the fuel was basically free. It took years of improvements to make the technology cost effective in other domains.

[0] https://acoup.blog/2022/08/26/collections-why-no-roman-indus...

Machines can work 24/7, don't get sick, don't get lazy, don't need training, don't need to be fed, etc.

Even in a world where slave labor was cheaper, machines were obviously better. Fewer people could produce the same output no matter how you look at it.

Machines break all the time. Particularly when you are faced with the metals available back then. They are a lot more reliable today, but we have had ~200 years of industrial revolution to learn how to make reliable machines. We also have a lot more population, and that means a lot more people thinking about how to make machines more reliable.

Modern machines are clearly better than slave labor today. However 2000 years ago a lot of things were different.

The machines need lots of fuel which either needs to be chopped from forests or dug out of coal mines. Both those tasks were labor-intensive and costly.

Some water mills were cost effective though.

>Slaves were abundant and the practice was widely accepted in paganism.

Slavery in various forms was widely utilized across all of humanity until the last few centuries, and in some ways it still is utilized today. We just don't call it slavery anymore.

"Paganism" has nothing to do with it.

Christianity promoted this teaching: "There is neither Jew nor Greek, there is neither slave nor free, there is no male and female, for you are all one in Christ Jesus"

This was a radically different teaching from other world views at the time, paganism being the main one in question during Roman times.

Paganism may or may not have specifically promoted slavery, but it did not offer any teaching that there might be a fundamental problem with it.

Unless you're deliberately cherry picking, Christianity was the poster child of slavery both explicit and implicit. Of course, they are not any more wrong than all the others who utilized slavery.

Framing slavery as rooted in paganism isn't accurate, and more importantly isn't helpful in having a worthwhile conversation. All it does is paint Christianity as some moral paragon, which it is not.

There's some truth to the argument that Christianity introduced novel concepts and ethical ideas that eventually led to the opposition to slavery, ideas that were not present in Graeco-Roman thinking, for example. The fact that those ideas took so long to come to fruition doesn't invalidate that line of argument.

Reply on news.ycombinator.com