Ancient Roman Valves (2013)
valvemagazine.com
valvemagazine.com
The existence of "Valve Magazine" is slightly more so.
(and to GP: perhaps one day we might discover the remains of ancient Roman Valve Magazine!)
Niche anything can be pretty surprising.
https://cloud.3dissue.com/24685/25516/33805/2020-v1-Winter/i...
Speaking as someone who had a stint at designing manhole covers and valves among other things.
https://i.imgur.com/gX26IYG.jpg
I found it to be absolutely amazing so I had to find out more about it.
If someone had described Hero's aeolipile to the people who built this plumbing, it might have made all the difference.
The wood heat is too low to get high pressure saturated steam, and lower pressure is not that useful and requires a huge boiler or specially prepared wood briquettes.
Metallurgically, Romans knew of brass and copper, which is enough for a decent steam boiler. It would be rather expensive to make.
Thanks for a tip! While I couldn't find exactly what you mentioned, I did find this picture of a bearing from a Roman bilge pump:
http://www.bbc.co.uk/ahistoryoftheworld/objects/0ZUWbEmiTXWf...
In 2000 years, they may say it of "plastic".
If the Romans had discovered the Bessemer process for making steel in quantity, the industrial revolution might have happened two thousand years sooner. They had a "steel industry", but could only make enough for swords and such. A Bessemer converter is much simpler than that valve. Would have changed history. The railroad era might have started around 150AD.
A similar effect could be seen in the different ways the American North and South evolved after independence -- the North, which didn't have slaves, industrialized, while the slaveholding South remained stubbornly agricultural right up to the Civil War.
The more expensive human muscle power becomes, the more attractive it becomes to replace muscles with machines. And a slave society is a society where muscle power will always be cheap.
Romans heavily implemented new processes for things such as mining, milling, and shipping. The slavery angle doesn't pass any form of smell test. If the claim is true, why would any society that ever had slavery ever do anything? Romans had waterwheels that drove machinery and used generated power to automate many aspects of their society.
The Romans obviously made extensive use of technology, and their peers didn't advance much more quickly than they did, with the massive capitalization of slave and other labors. Nor did the vassal states within the "boundaries" that we find in history books.
So at the time they could afford it, they were expanding or fighting civil wars, later they were scrambling to hold it together.
There is also a transportation problem. The inputs for steel manufacture are large. To be economic you needed fuel and ore in close proximity.
Sweden was a power house based on high quality iron ore deposits and vast pine forests. Which they cut down pretty much completely. I think India with fast growing tropical forests was also a large exporter of iron.
Britain initially had large forests and iron ore. But also huge reserves of coal almost on top of their ore deposits. That allowed them to keep going once the forests were gone.
Oil and gas are reducing our reliance on coal.
Barring some new discovery about energy sources, nuclear is probably the only thing that can appreciably reduce our reliance on fossil fuels.
Does anyone know if those are as far off/unrealistic as they sound?
As for something like tethering orbiting objects or the like, it is all still theoretical. A space elevator requires similar material technologies and nobody has found a way to feasibly build such a large, strong, and light tether or chain. But that isn't something I would expect to see any time soon.
Although now that I think about it, you could potentially nudge a conveniently positioned space rock into a sacrificial eccentric orbit around earth and harvest energy off that ever time in skims by until it finally crashes down into the earth.
> When the tether intersects the planet's magnetic field, it generates a current, and thereby converts some of the orbiting body's kinetic energy to electrical energy. Functionally, electrons flow from the space plasma into the conductive tether, are passed through a resistive load in a control unit and are emitted into the space plasma by an electron emitter as free electrons. As a result of this process, an electrodynamic force acts on the tether and attached object, slowing their orbital motion. In a loose sense, the process can be likened to a conventional windmill- the drag force of a resistive medium (air or, in this case, the magnetosphere) is used to convert the kinetic energy of relative motion (wind, or the satellite's momentum) into electricity. In principle, compact high-current tether power generators are possible and, with basic hardware, tens, hundreds, and thousands of kilowatts appears to be attainable.
Maybe cosmic radiation interacting with the magnetosphere is adding to the "wind" in the analogy; not sure. Agree that the explanation makes it sound like you'd basically just be turning launch energy into electricity, which doesn't sound useful for generating power to send back to earth.
Nudging space rocks into orbit to generate electricity is a cool sounding idea. I've heard similar proposals for space mining if and when it becomes a thing just to make transporting the material a lot easier. Not sure how plausible that is either.
Regardless of what form it takes, I really hope we get some serious and practical space infrastructure at some point. I think having a practical reason to go into space beyond just gathering astronomical data and doing experiments will help keep space programs from stagnating. Plus it'd be super cool.
But if you ain't got the energy, then making any devices, however clever, isn't going to change the tide. Antique and medieval civilizations had some rather elaborate mechanisms like the antikythera, the trebuchet, rapid-fire crossbows in China etc. But without a major source of low-cost energy, none of them succeeded with an industrial revolution: large-scale coal-mining was what did it in the end.
This was long before Bessemer and less expensive steel.
There is a Newcomen on display (it's not small...) at the National Museum of Scotland in Edinburgh.
Edit: cf. https://www.nms.ac.uk/explore-our-collections/stories/scienc...
Watt's engines were about 10-20 hp, and about 10% efficient. Peak efficiency of a triple-expansion steam engine approached 25%. The best thermal engines today (combined-cycle steam turbines) approach 50%, and have a far better power-to-weight ratio.
Not really; people had bunches of coal giving off lots of thermal energy forever. They used it in the obvious way, burning it for heat in winter. This didn't lead to much in the way of technological advance.
> and optimal ones, of decades or centuries (i.e. much longer than Roman history).
How is "centuries" "much longer than Roman history"? Roman history goes on for more than 700 years, and that's just the history of Rome as a major international power centered on the city in Italy. The Byzantine Empire, or -- as it called itself -- the Roman Kingdom, with extensive cultural and institutional continuity, went on for another 1000 years after that.
Only the usage of more efficient crops like potatoes and the import of fertilizer like guano enabled the people of the industrial revolution to work in factories instead on the fields.
No pre industrial civilization was able to feed so many people not working in agriculture.
Horses are faster, but oxen are way more efficient. But were widely used right until transport mechanization, neither replaced the other.
What gain is there in being able to do the trip twice if you carry less than half the amount? (Yeah, it's rhetoric, there is some gain, for some cargo, and loss for other cargo.)
Something along the lines mentioned here: https://en.wikipedia.org/wiki/Horse_collar#Earliest_predeces...
Coal throughout Europe is mostly in the northern band, from Scotland, especially in Cornwall, France, Germany, and present-day Czech Republic and Poland. Where industrialisation happened, for the most part.
England's coal mines were near the sea, and river/canal transport, and could be moved readily by ship elsewhere in the country.
Coal in the US didn't come into wide use until after substantial rail infrastructure was built out (the 1880s), with high-grade Bessemer steel, capable of bearing heavy coal cars. Until then, wood, usually locally-sourced, was the preferred fuel.
The principle differences are:
- Rail. Which is roughly the equivalent of a canal or waterway, though with higher speeds. About 1/2 as efficient as large-scale cargo ships.
- Air. Extraordinarly expensive, but fast. Also very effective at spreading disease.
Within a few years, the Bessemer process reduced the cost of steel by something like 85%. Most of that savings was a result of reduced coal usage.
> There's little to no coal in Italy.
Nor is there copper or tin. Cornwall was a significant source of tin during the Bronze Age, and was a significant part of the reason Rome invaded Britain. (there was accessible copper in Cyprus, just not in Italy itself.)
The story about "flexible glass" during the reign of Tiberius Caesar is probably false, but illustrates how technological innovation is expected to be received when there are powerful gatekeepers to broad technological change: https://en.wikipedia.org/wiki/Flexible_glass
You see similar actions by technophobic rulers in Ming China following the voyages of Zheng He or even in 16th century England: https://en.wikipedia.org/wiki/William_Lee_(inventor)
Entrenched interests usually would much rather maintain the status quo than enable anything potentially disruptive. The industrial revolution started because it was infeasible for any one powerful group in England to oppose innovation.
Reading it, I thought how fantastic it would be if that material had actually been around for centuries. Then of course, the end of the article links to gorilla glass, a material we all use daily and barely even think about. Do we live in mythical times?
But yeah, todays access to clean drinking water is largely an economical issue, not so much a technical one.
It’s crazy to think how medicine didn’t really advance for ~2000 years, and then vaccinations, antiseptics, and anesthesia (and later antibiotics) came into use and medicine advanced rapidly. Oh, add in a dash of germ theory and the scientific method, and stir. The Romans were really quite amazing!
B) Excluding infant mortality, you were generally good to go to 55-60 in Rome, about where the US was in 1920's or 30's time frame.
C) that's plenty of time for acute or chronic lead poisoning to F anybody up.
Highest mortality was among infants and young children. Once you reached age 20, odds were quite good of living to 60. Elders of 80+ years were common.
These are data from England and Wales, 1700 to present, but would all but certainly have been similar for ancient Rome:
https://ourworldindata.org/uploads/2013/05/Life-expectancy-b...
The issue with Flint was that they increased the acidity of the water by changing the water source, which removed that barrier.
https://www.theglobaleducationproject.org/egypt/articles/hrd...