Dr Peter Saunders gives us an insight to the wide variety of measurement systems that existed in Europe a few centuries ago.
Discussion point: Why were measurement standards useful for trade within a town but difficult for trade between towns?
Transcript
PETER SAUNDERS
So if we go back more than 250 years ago, there’s no particular date on there, but if you looked around the old towns in Europe, you would often find standards of measurement. So each town had their own standards for measurements of length, mass and volume, and they were often embedded in some structure in the town square. So for example there might have been an iron bar, which was representing a length standard cemented into the foundations of the town hall, for example, or perhaps there’d be a statue with sort of two marks on the statue indicating a length.
So for example, if you go to Dubrovnik in Croatia, you’ll find this thing here, this statue, which is called Orlando’s Column. And so Orlando was a knight – this thing dates back to the early 1400s – Orlando was a knight, and legend has it that he saved the town of Dubrovnik from a 9th century siege that sort of went on for 15 months. And so the citizens in town were very grateful so they erected this statue in his honour. Unfortunately, that legend is probably not true, and in fact, the statue represents a town that was under the protection of the Hungarian-Croatian king, so it’s really a sign of liberty.
So in this town, the standard of length was the length of the forearm on the statue so traders used to compare their lengths of fabric to that length. So because, as I said before, Orlando was a signal, a sign of liberty, you’ll find statues of Orlando – he’s also called Roland – in other towns of Europe. So if you go to Bremen in Germany, there’s another statue of Roland or Orlando, and the standard unit of length in Germany was the distance between those two points on his knees.
And so in modern measurements, what was called the Dubrovnik ell – e-l-l, which is the unit of length – was 51.2 cm, and in Germany, the Bremen ell was 55.9 cm. So it’s the same Roland, same statue but different units.
If you go to Trafalgar Square in London, you’ll see a plaque on the north wall, and it has some of the imperial units – the foot, 2 feet and the 3 feet or the yard. And also, if you look along on the ground in Trafalgar Square, there are plaques that have larger distances, such as 66 feet, which was called a chain, and a hundred feet. This thing was installed – I’m not going to put the date on the screen – but this thing was installed in 1876, so I just want you to remember that date because we will come back to it.
So it was really useful for trading within a town to have your own local standards, but it meant that it was difficult to trade between towns because each town essentially spoke a different measurement language. And at one point in Europe, there was something like 27,000 different standards for volume, so it was really difficult. Also, having the local measurement units that everyone used within a town was good for the local authorities to collect tax – if you can measure it, you can tax it – and so it was very useful for them.
Acknowledgements
This video clip is from a recording of a presentation by the Measurement Standards Laboratory of New Zealand (MSL) in celebration of the redefinition of the International System of Units (SI), which happened on 20 May 2019. The presentation by Peter Saunders and Farzana Masouleh of MSL was filmed at Unleash Space, Faculty of Engineering, Auckland University.
Filming and editing by Jonathon Potton of Chillbox Creative. MSL produced these videos to share the story of metrology development.
