Measurements in high fantasy/secondary world fantasy

Have you thought about talking about distances in terms of the time it takes to journey? ie, they can be seen half a day's journey away. (Not always literally, of course, because you know how things are with mountains--- you can see Kansas from the top of Pike's Peak, but you can have difficulty seeing a quarter mile away if there are trees and rocks blocking your view.)

I think readers would be able to get Ri from the context, it doesn't need to be exact, right?

It's always a balance between staying consistent in the world you create and not confusing the reader. I would continue your research on different measurements throughout history to farm ideas. Then for your very primitive race, I'd try to find a context for why they would measure things a certain way. Things like weight in stones, for example, stolen from the British weight measurement, would be a realistic way to compare weights of things readers would easily understand. For distance I'd probably go with the position of the sun or line of sight like Lonestarlibrarian suggested.

For your Japanese-based culture, if you wanted to avoid feet you could always use comparisons like trees, mountains, buildings, people, ex. two men tall! Or something.

As a final note: sometimes it's worth the past of least resistance. This is YOUR world. If you decide you want a society to have miles, then they have miles. Most readers probably won't call you on establishing details like that. Not all societies advance in the same fashion or discover things at the same time, so it's plausible in your world they just came up with the concept of feet, miles, you name it, before our own. IMO: this doesn't necessarily have to be explained. I know when I read a new fantasy/scifi in a secondary setting, the first at least 50 pages if not more part of me is always thinking: "okay, what are the rules in this world. Where we at? How do things work? As long as you don't break the rules you establish, most readers will go with you for the smaller facts. I think.

I will say, these are decisions that are best made as soon as you can in your draft... I am a cautionary tail. I decided retroactively that my world didn't have traditional clocks, which means no hours, minutes, or seconds. It is astounding how many times times I searched for these words in my manuscript, and STILL managed to miss references to 12 hours clocks. I did keep noon as a reference...because...BECAUSE.

'Miles' is a generalization. The samurai are on horseback?
"An hour's ride away, and coming fast!" Or whatever time seems reasonable. This can also be used to judge the leader's reliability.
"We sought a more defensible location, and waited".
"They were on us much sooner than that". Etc.

As to height: "The oni was twice the height of a tall man".
"The tree was as tall as five men."
You're giving an idea, a sense of scale, rather than measuring up a tree for it's use as lumber. Height is different from board feet. The guy who is sourcing wood for the castle would know the second, the samurai is okay with just the first.

I'd suggest reading some fantasy novels that use less common (or invented) measurement terms. It's all about providing context the first time (or two) you meet them. If a character is told that the nearest town is ten snerklongs away, do they groan in despair - that'll take at least a day of hard riding! - or do they sigh in relief that the journey's almost over and they'll be eating at the inn in half an hour? Is the hooded stranger on the path, standing about five gorlings high, considered "tall for an elf, but short for a human" (which also tells you that elves are smaller than humans in this world)?

Sometimes one can avoid it altogether with comparisons (tall as a tree, small as a bug), but there are some characters/POVs and situations where more specific measurements would make more sense.

In my story the book itself is an in-world narrative retelling of real historical events so there's references/footnotes, so i just put one saying "I converted this to our modern units for ease of the modern reader." But we all do this in some ways with stories set in secondary worlds. No one is actually speaking modern English, or English at all! But our stories are written in English and use English narrative styles/techniques. See this tv trope page. So if you use mile/kilometer I don't think anyone is going to hold it against you unless they're specifically going out of their way to nitpick you, like how they're not going to hold it against you if you use a word whose etymology is based off of a real world person/place/event which doesn't exist in your world.

I do use "head" for comparing character heights (he was a head taller than her) and head is roughly 8", but it's immediately obvious what that looks like. I also used hands for a horse (which is 4") since that's a horsey term AND it's immediately obvious what that looks like.

Instead of saying the oni are 12ft tall perhaps a comparison such as the height of bear standing on its hind legs, or twice the height of a large horse. once their relative height is established you can compare other beings and objects to them. For distances between places I like to use the amount of time it takes to walk, ride or sail- half a days travel by horse, three days sail and so on.

The original 'mile' was based on the distance from the running pace of a Roman soldier - 1000 paces = 1 mile.
A furlong was the average distance of a plowed field.
The weight measurement of a stone was based on... well... a rock.

K.S. Crooks said:

Instead of saying the oni are 12ft tall perhaps a comparison such as the height of bear standing on its hind legs, or twice the height of a large horse. once their relative height is established you can compare other beings and objects to them. For distances between places I like to use the amount of time it takes to walk, ride or sail- half a days travel by horse, three days sail and so on.

Click to expand...

IF I have to do measurements of any kind (and when I think about it, I find I can generally not bother with them), then I do it all in relation to what is common to the POV character. I never give the height of a character, but if he's always looking up at someone, you know he's short. Likewise, if he's looking slightly down at them, you know he's tall. If I don't mention it, the reader assumes he's average height. Other people's heights are handled in relation to the POV char's.

As far as travel distance, it's how long does it take to get there by what mode. The heavy sigh of needing to spend the next three days walking or a hard day's ride to the destination is enough. One culture (Celtic based) I have prides itself on having inns about 1 day's walk along the major roads and how far away someplace is is measured in how many inns you'll have to stay at.

Measurement is a subtle reflection of your culture. A reader doesn't need to know down to the centimetre how far or tall something is. They just want a good sense of perspective so they feel confident in their envisioning of the story.

You have to be careful to consider not only the language you use, but whether the way you think about distance is anachronistic. For example, measuring things in units is a relatively modern concept. You need to put yourself in the mindframe and think the way people in your characters' culture will think. It's not always enough to just replace "miles" with another word. How do they think of distance?

For example, I write prehistoric fiction and in my story set 40,000 years ago there are Homo sapiens and Neandertals. The Homo sapiens are nomadic, living in one place for a few months or a year or so, then moving on. They measure distance in how long it takes to walk somewhere, e.g. "that's nearly half a days walk away", and it's relative to themselves, i.e. half a day's walk away from where they're standing right now. The Neandertals live in a cave in the mountains and have done for their whole lives, so they don't really think of distance in the same way at all. Their geography is permanent, they know where everything is and where it is in relation to everything else, so describing the distance between things isn't really necessary. If they had to describe where something is, they'd say which landmark it's nearest to. They're an isolated population so rarely talk to people who don't know their local area. And they don't speak the same language as the Homo sapiens people who wander in and out of their lands from time to time so attempts to communicate with them are hindered by much more immediate issues than whether or not the Homo sapiens people know the local geography like they do.

So the question is, how do your people think about their local geography and distances? When you know this, it becomes clear how they would describe distances.

For describing non-human characters as 12 feet tall - what comparisons do you have to indicate this? If they are all 12 feet tall and this is normal for them, then they won't think of it at all. From their point of view, if/when they come across humans, then they'll describe humans as tiny, rather than describing themselves as large. Ditto anything/anyone else they come across that's small to them because they're big. They will think of themselves as normal sized. If they are being described by a member of a smaller species, then it's different. How would the member of the small species, in their own culture, describe the height of the taller one?

If you're using a Japanese setting and you want the measurements to help reinforce that, then I would just use them! You can provide a footnote or some other note that converts your measurements to the most common modern world equivalents.

Once the reader has fixed in their mind that Ri = 1/2 KM then they will just do the math on their own. Most readers will approximate it mentally to 2 Ri = 1km 4 Ri = 1 Mile.

It's a little bit more mental overhead for a reader so I would be careful to not rely entirely on the measurements but also have characters reference how long the journey will be, how tall the building is, etc. People do that in real life all the time anyway. "Seattle is 2 hours away" is way more commonly said in my town than "Seattle is 96 miles away". So someone saying, "The town is 40 Ri away" could get a response like, "Ugh, that's an entire day's walk!"

Especially if you do that kind of comparison early in the beginning I think the reader will develop a good idea of what your distances are like.

I think you can definitely use Japanese measurements. In general, readers are good at figuring out context.

With that said, I see nothing wrong with using feet, inches, miles (or meters, centimeters and kilometers, either). Your characters are speaking English, after all. (Unless this is one wildly experimental novel.) I'm okay believing that their measurement system translated over along with the language.

I've seen different approaches in fantasy and in historical novels. Some use a system of measurement appropriate to that time and place, possibly with some kind of appendix that provides comparisons to modern measures. Sometimes, though, a "translation" principle is applied and modern measures are used. This can feel anachronistic, depending on how it is handled (I find it knocks me out more when metric units are used, maybe because they "feel" more modern than miles/feet/inches etc.) Sometimes one can avoid a measurement entirely, and provide a descriptive height comparison, such as "He stood taller than a mature oak" or "his head brushed the second-story eaves of the farmhouse."