Rulers of the Ancient World: period correct measuring tools

I have two anecdotes. One is a shipyard in Denmark, possibly in the 1700's, where the master builder would hammer a stake in the ground, walk as many steps as needed for that ship, and hammer another stake. The rest would follow geometrically.

The other is a builder of harpsichords, late 1900's, who explained that when starting a new instrument, he would define the "inch" for that one, the width of the "white" keys. 8 of those would make the width of an octave, and the usual 5-6 octaves would give the width of the keyboard. From that he could figure out the length of the instrument, and the curve of the side. All this with nothing more than a compass and a straight edge. He claimed it was the more historical way to do it, as they did in the 1600's. His instruments were well regarded by musicians today, and fetched a good price.

Brendan (the maker of these) is a fascinating, very smart guy. He's a very talented woodworker and wrote a great book on James Krenov. I was lucky to take a class he taught a few years ago, and I enjoy following his Instagram page to see the new projects he has going on.

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

I think the coolest thing from an experience perspective as far as a built environment with this is the opportunity to have spaces with different ratios and spacing.

I’m reminiscing about realizing from an American perspective why buildings in Europe felt so different. Old buildings sure, but new buildings feel weird! It finally dawned on me that the difference between imperial and metric had made its way to the build environment in subtle but pervasive ways that once seen could not be unseen. Case in point, European doors are wider, switches are lower, door handles are lower, rooms are just slightly off. Of course the reverse would be also be true. But contractors rounding to whole units for simplicity had standardized on a set of ratios that made things feel odd.

Would be cool to have an installation that embodied this. It’s subtle but talk about driving people crazy.

These are beautiful - but the project kind of misrepresents how ancient measurements worked.

Outside of building sites in Medieval Europe it would be common for the head architect to have the outline of his hand on a sign. The idea being that even "crude" measurements like hand-widths and thumb lengths would be universally agreed upon for the project.

You can see some of this at work watching documentaries of the Guédelon Castle project - you see just how little precise measurements were actually needed. A lot of tasks we are used to accomplishing through high precision measurement, they instead use clever tricks of geometry. And jigs - lots of jigs.

In this way, ancient craftsmen were genius - often understanding some pretty profound principles of geometry through experience and intuition alone. Measurements, such as they existed, were always a very "local" affair.

It wasn't until empires and mass manufacturing that the need for "standardized" measurements. The intelligence of the individual craftsman became less important - the ability to follow instructions became more. In a way modern measurements are a form of artificial intelligence - an automation tool.

these are great. geometry is culture. there are some mythical proportions measured in cubits, handbreadths and other units of measurement (pillars of the first temple at jerusalem, etc) that put reading the old testament in perspective, where they were writing about physical objects we can use those measurements to reason about today.

I hope there are more editions of these rules and related ones in the future.

It's neat that the Egyptian measure was subdivided in an increasing fashion, almost logarithmically. I wonder what the error bound is if you use the Egyptian rule as a slide rule.

I’m excited to see others as focused on this sort re-evaluation of the correct balance between digital and analog tools and manufacturing. This is exactly the area I’m working but this guy is documenting it.

That's a great title

Measurement by duplication is another fascinating sub-area of tools and techniques. Templates, pin guides, profilers, slotting jigs, tick sticks, ...

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.

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

TLDR - an ancient measuring rod project (modern reproductions)