Rulers of the Ancient World: period correct measuring tools

This was an impressively-"Garden Path" title, given the noun/verb ambiguity of "correct" and the modifier(?)/verb ambiguity of "measuring" :)

While I am no apologist for the measurement system we use here in the United States, I realized something interesting when trying to explain why almost all of our units consist of easily divisible sub-units. Imagine you needed to split something up into halves, thirds, fourths, sixths, etc.. If you imagine doing this with paper, it's fairly easy.

Now imagine Metric, and the need to split something into 10 even pieces. We can make this a little easier knowing that we just need to split into fifths first, and then halve each of those. Do you know how to fold a piece of paper into fifths?

It can be done, and it's remarkable how to do this with a straight edge and a pencil. However it is definitely more time consuming than being able to fold using easily divisible numbers. To that end, once you have a decimal ruler you can just use that, but I can see why decimal based measurements were not more common in the past.

All that being said, I really wish metrication had been completed here in the US before I was born.

thats a really cool project. I would've loved making them while taking my history electives in college. There's something really nice about making something that gets tied to what you're learning.

Since they talk about Roubo, can I ask if any other amateur woodworkers just don't use a ruler?

I used to 3d model everything and make simple dimension drawings for parts. Since I started mostly using hand tools I just stopped measuring. Each part is a proportion of the other parts. I find it a whole lot easier, more forgiving, and easier to correct. I do use dividers, however.

Just curious if I'm the only one. Of course my disclaimer that the most complicated thing I made without a ruler is a dutch-style workbench out of oak. The most complicated thing I made from my old way of cad was probably a set of fairly complicated shelves

The nice thing about geometry (as opposed to arithmetic) is that it's easy to guess something a little larger[0] than 1/10, repeat a series of ten of those units, and then line its end points up at an angle to your work and, letting similar triangles do their thing, transfer[1] from there...

[0] eg, 1/8 would work, if you insist on subdivisions

[1] assuming space-time is effectively euclidean at the scale you're doing this, which even on HN ought to be a safe bet?