What building knowledge you have to pass on to a civilisation a thousand years ago?

In My Humble Opinion
21

FWIW, glass making wouldn’t be a problem. The Romans had been glazing glass into windows since the first century AD. Besides, any medieval glazier who walked into my stained-glass shop would recognize most of my hand tools and equipment anyway; the craft itself really hasn’t changed that much in a thousand years.

Like DreadCthulhu, I could make gunpowder, and with the help of a competent blacksmith of the time produce firearms, artillery, and explosives. It’s unlikely that we’d be able to produce repeating weapons right away, though, with the rest of the technology of the time, so the Eldritch One has got the right idea about tactics.

Steam engines and iron-clad boats are also an excellent idea. I’d also build a hot-air balloon and introduce the concept of flight. Just folding a sheet of paper into a paper glider would make an effective learning aid.

I think I’d also enlist the help of the local potter and build a flush toilet to introduce modern sanitation ideas.

All of this, of course, depends upon me staying out of the hands of the superstitious local clergy who might think I’m a demon and consign me to the stake.

22

Another idea I just had, of a very useful technology that I could put together from some simple parts would telegraph. Or maybe even a simple telephone. Once you get the wires strung up, this would give you an enourmous commications advantage over everyone else. Of note, though, the telegraph would probably work best if you ended up in area that was using an alphabet for writing; Chinese wouldn’t work too well with telegraph, without resorting to making a new alphabet.

23

After thinking about it a little, I was ready to say basic hygene, i/e toilets, running water, handwashing, sterilization. I Know I could come up with a crude microscope to show germs, make soap, figure out basic plumbing and sewage. So what would be the result? Well better quality of life, longer lifespan, and decreased mobidity of disease.

Which gives you famine, too many people for the resources available.

I could probably fix that with better farming/animal husbandry techniques. I might be a bit shaky here on some of it, but sanitation would help the animals, improve grain storage, and I do know a bit about farming and selctive breeding. The result? Overpopulation, You’ve eliminated 2 of the biggest killers of the time. Disease and famine.

The fix? Might as well stick to the biblical theme. War. Invade the neighbors, take thier land, spread your borders, get more resources and land. I could help with military tech, some tactics. The result?

Well probably then you’d move into politics and power. Here I’d be lost.

I guess the thing I see is the need to go slow, and keep a balance, you get no benefit if they destroy themselves and you in the process. I don’t think there is a natural science of that era that I couldn’t make a contribution to, or a simple machine I couldn’t build, so I don’t know, depends on your goals. Maybe a sawmill here, a bit of sanitation there, and probably as panache45 said, maybe just set them out on the path to find it in their own time(after I have set myself up well first though).

24

And a spellchecker, I’d invent a spellchecker too.

Did I mention I have been playing civ a lot?