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Historical Tech Tree

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Re: Historical Tech Tree

#91

Post by jacquesm »

NooneAtAll3 wrote: post #84
mitthrowaway2 wrote: post #25

Earlier quoted context omitted.

Interesting. On that note, Da Vinci's design (which I was fortunate enough to see a replica of at a local museum) was also very clever, being suited not only for screw cutting but also screw origination, as it could make new screws more accurately than the two leadscrews in the machine itself, and swap them out to improve its own accuracy. But I suppose it doesn't extend that date even further back because it wasn't…

having no experience in precision manufacturing and metrology... how does one become more precise than input tools?

Just some examples: take a string, don't bother to measure it, just any length between 1 and two meters or so would do. Take a pencil (or a piece of charcoal if you really want to go native) and a smooth branch. Stick the branch in the ground, tie the string around it so that it can slide with little friction and put the pencil in a loop of string on the other side. Now use this to create a circle. You started off with very rough elements not specifically sized for any purpose and ended up with a high precision representation of a mathematical concept.

Another: take a bunch of roughly cast metal balls. Put them on a sieve and let it vibrate until the balls have all passed through the holes in the sieve. Behold: metal spheres, so precise that you probably can't really measure the degree to which they are not spherical without resorting to instruments that you're not supposed to have in this scenario. Then sort by weight (which is a proxy for size). Now you can make ball bearings.

Yet another example: you can cut a lens for a telescope to within ridiculous precision using very primitive methods (https://www.instructables.com/Grind-and-Polish-a-DobsonianNe... ).

Put another way: it is always possible to increase your precision as long as you don't particularly care about absolutes or temperature effects.

Re: Historical Tech Tree

#92

Post by jacquesm »

School-Cotton wrote: post #69

Somewhat tangential, but can anyone explain or give any insight into how candles were invented? This has always puzzled me. The idea that if you put a piece of string in some wax, and light it on fire, the string will get hot enough to melt wax, and the molten wax will be sucked into it by capillary action, and burn, before the string itself burns, seems very counterintuitive and hard to come up with before a modern…

Because the people from 700 BC were just as smart as we are. Observing the world around you is one of the best sources for ideas and there are predecessors to 'real' candles that must have fertilized the ground for the discovery. For instance, a stick dipped in rendered fat could serve as a torch. Not quite a candle but a significant step on the way there.

Re: Historical Tech Tree

#94

Post by ghaff »

jacquesm wrote: post #87
wongarsu wrote: post #29

Obviously something of this magnitude will have blindspots. This tech tree seems to be vastly underselling the impact of advances in metallurgy and precision machining. As well as most of what you might call "basic science". This leads to e.g. the Gas Turbine just appearing out of nowhere, not depending on any previous technology

Almost all science is tightly bound with advances in material science, often the driving each other in alternating steps like interlocking gears. One engine driving those gears is war, another is population growth and education. There are obvious exceptions, such as Math, Philosophy (insert all links lead to philosophy here). But even Math is seeing progress in materials science as a component now (computer derived p…

Even aside from the big advances, look at things like clothing in the past few decades. Outdoor clothing has changed enormously but so have so many other day-to-day things--a lot of which are about electronics but that's materials-related as well.

It's an interesting question. Why couldn't the Romans have invented $X? And the answer is mostly the tech tree. There are probably exceptions around things like germ theory of disease and so forth but it's mostly true.

Re: Historical Tech Tree

#95

Post by Qwertious »

NooneAtAll3 wrote: post #85
mwkaufma wrote: post #28

I'd expect something things like Chinese Writing to be a big upstream dependency, but here it's a terminus. Detecting a western-bias in the sourcing.

what's the technological difference between Chinese Writing and Western Writing? why are they separate?

(Not an expert but) Chinese writing is hieroglyphic, wheres 'western writing' is phonetic. Western writing has a very small character set and is thus well-suited to a printing press, whereas hieroglyphics have thousands of characters (for thousands of concepts) but aren't fundamentally linked to the language like western characters are.

Re: Historical Tech Tree

#96

Post by Qwertious »

School-Cotton wrote: post #71
drcode wrote: post #70

Earlier quoted context omitted.

Pure speculation, but I would guess people first mixed wax and lamp oil in different ways to still get the burning effect of oil, with less of the cost of the oil, then added a wick to help light the oil/wax. Then eventually that product morphed over time to the point where they realized the oil wasn't actually a necessary component

Good idea, it sounds plausible! But it still leaves open the question of how oil lamps were invented. How did someone figure out that a wick would be helpful?

1. Someone dips a rope in flammable oil before lighting it, and sees that it's quite flammable. 2. Some other time, someone tries to use a rope dipped in flammable oil as a fuse to trigger the lighting of the oil once it burns back to the oil 3. They notice that the fuse keeps burning but doesn't burn back - in other words, the wicking effect 4. They shorten the rope and reshape the pot, and that's an oil lamp.

Re: Historical Tech Tree

#97

Post by Qwertious »

dmurray wrote: post #78
School-Cotton wrote: post #66

Genuine question: how does it make sense that both bread and alcohol fermentation were invented before the domestication of any grain? Were people making bread (and beer!) with gathered seeds?

Wine is much easier than beer, because ripe fruit will ferment on it's own. Even wild animals get drunk sometimes; it's sometimes said that wine was discovered but beer was invented. So alcohol without any grain is easy, but I don't know the answer for beer. On the other hand, why would you domesticate grain unless you already knew you could turn it into beer or bread?

Grain can be turned into porridge (so basically just soaked) and eaten, bread and beer is optional. In fact, IIRC classical-era armies would eat their grain as porridge instead of spending hours in camp baking it into bread. For obvious reasons.

Re: Historical Tech Tree

#99

Post by jacquesm »

ghaff wrote: post #94
jacquesm wrote: post #87

Earlier quoted context omitted.

Almost all science is tightly bound with advances in material science, often the driving each other in alternating steps like interlocking gears. One engine driving those gears is war, another is population growth and education. There are obvious exceptions, such as Math, Philosophy (insert all links lead to philosophy here). But even Math is seeing progress in materials science as a component now (computer derived p…

Even aside from the big advances, look at things like clothing in the past few decades. Outdoor clothing has changed enormously but so have so many other day-to-day things--a lot of which are about electronics but that's materials-related as well. It's an interesting question. Why couldn't the Romans have invented $X? And the answer is mostly the tech tree. There are probably exceptions around things like germ theory…

Any post about tech trees sooner or later mentions 'I, pencil', so let's get it over with:

https://fee.org/ebooks/i-pencil/

Re: Historical Tech Tree

#100

Post by slightwinder »

School-Cotton wrote: post #71
drcode wrote: post #70

Earlier quoted context omitted.

Pure speculation, but I would guess people first mixed wax and lamp oil in different ways to still get the burning effect of oil, with less of the cost of the oil, then added a wick to help light the oil/wax. Then eventually that product morphed over time to the point where they realized the oil wasn't actually a necessary component

Good idea, it sounds plausible! But it still leaves open the question of how oil lamps were invented. How did someone figure out that a wick would be helpful?

The first oil-lamps were basically a bowl with animal-fat and plant parts as wick. It's not hard to imagine how ten thousands years ago a hunting tribe could discover such a device by accident or on purpose.
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