Everything Everywhere Daily: History, Science, Geography & More - The History of the Compass

Episode Date: July 21, 2022

One of the most important inventions of early humans was the compass. The compass has aided human navigation around the Earth for centuries.  Despite being a critical technology in the development of transportation, it actually took centuries between its discovery of its underlying principles and its eventual use as a practical tool for navigation.  Despite their origins over 2,000 years ago, they are still a vital tool today.  Learn more about the compass and how it helped humanity find its way on this episode of Everything Everywhere Daily. Subscribe to the podcast!  https://link.chtbl.com/EverythingEverywhere?sid=ShowNotes -------------------------------- Executive Producer: Darcy Adams Associate Producers: Peter Bennett & Thor Thomsen   Become a supporter on Patreon: https://www.patreon.com/everythingeverywhere Update your podcast app at newpodcastapps.com Search Past Episodes at fathom.fm Discord Server: https://discord.gg/UkRUJFh Instagram: https://www.instagram.com/everythingeverywhere/ Twitter: https://twitter.com/everywheretrip Website: https://everything-everywhere.com/everything-everywhere-daily-podcast/ Everything Everywhere is an Airwave Media podcast." or "Everything Everywhere is part of the Airwave Media podcast network Please contact [e-mail] to advertise on Everything Everywhere. Learn more about your ad choices. Visit megaphone.fm/adchoices

One of the most important inventions of early humanity was the compass. The compass has aided human navigation around the earth for centuries. Despite being a critical technology in the development of transportation, it actually took centuries between the discovery of its underlying principles and its eventual use as a practical tool for navigation. And even though it was discovered over 2,000 years ago, compasses are still a vital tool today. Learn more about the compass and how it helped humanity find its way

on this episode of Everything Everywhere Daily. What if your perceptions about the past were wrong? ThruLine is a podcast that takes you back in time to uncover the parts of the story that may have gone unnoticed. It effectively turned day into night. And how it shaped the world now. Time travel with us every week on the ThruLine podcast from NPR. Before I get into the history of the compass, I should explain a little bit about how it works. As I'm sure all of you are aware, a compass uses a magnetic, metallic piece of metal that will

orientate itself in the presence of a magnetic field. This effect will manifest in the presence of any magnetic field, including artificially created ones. However, unless you happen to be standing next to something magnetic, the magnetic object is going to align itself with the natural magnetic field of the earth. The earth can be thought of as a giant bar magnet. Just as a bar magnet has a north and south pole, so does the earth. The magnetic north and south poles of the earth are not the same thing as the geographic poles.

The geographic poles are steady, but the magnetic poles usually are some distance away from the geographic poles, and they're always moving. So, in summary, a compass is just a small magnet that aligns itself with a very big magnet, which happens to be the Earth. The compass effect, which I just described, was first discovered sometime during the Han Dynasty in China about 2,000 years ago. Unlike other great Chinese inventions, who discovered the compass effect and exactly when it was discovered isn't precisely known. What we do know is that the Chinese found that if a lodestone were hung by a string, it always pointed south. And this was known as the south-pointing fish. Here I should note the obvious thing, that the Chinese define the direction which the rock would point as being south. Today we usually define the direction of a compass needle as pointing north.

Neither of these statements are in conflict. A compass needle aligns itself with a north-south axis, so it's always pointing both north and south, and which you choose to focus on is just a matter of convention. Loadstone, the rock which exhibited this behavior, has a high concentration of iron. In particular, the iron oxide known as magnetite. Iron has two common types of oxides, magnetite, which is black and highly magnetic, and hematite, which is rust-colored and not quite as magnetic. hematite has two iron and three oxygen atoms, and magnetite has three iron and four oxygen atoms.

The Chinese discovery of the compass effect was mostly just a novelty for centuries. It was interesting that this rock would always point in a certain direction, but there really wasn't any practical use to it. The primary use of the south-pointing fish was for divination in the form of geomancy and feng shui. Geomancy is simply using signs in the ground to tell fortunes. Feng Shui is the ancient art of arranging things according to lines of energy, and to do so, you needed to know the direction. Before I go further in talking about the history of the compass, I should note that the compass effect is a natural phenomenon. Unlike other Chinese inventions like the printing press or gunpowder, this was discovered, not invented. That means other civilizations might have discovered the effect as well.

And there is some evidence that the compass effect could have been discovered by the ancient Olmec people in Central America. potentially a thousand years before the Chinese. If they did, it was probably used for geomancy purposes like it was in China. The next advancement after the south-pointing fish was the magnetic spoon. These were literally spoons carved out of lodestone that could balance at the bottom of its bowl. The spoon would then rotate until it was pointing north-south. These are very interesting, but ancient forms of fortune-telling and magnetic spoons are not why the compass is worthy of an episode. That has to do with navigation. And that began with a discovery during the Tang Dynasty of the 7th century

that if an iron needle was rubbed with a loadstone, then it too would become magnetized. A magnetized needle was far easier to use than a rock or a spoon. Moreover, a needle was small enough such that it could be made to float on water, either using the surface tension of the water or floating on something light like a leaf or a piece of paper. A floating magnetized needle became known as a wet, compass. Likewise, the needle could be hung on a piece of silk thread, which would achieve the same purpose, and this was known as a dry compass. Still, these magnetized needles were again first used for geomancy, not navigation. The first evidence of magnetized needles being used for navigation on land

was documented in the 11th century, and the first maritime use was documented in the 12th century. The Chinese historian Xu Yu wrote in the book Pin Zhao Table Talks, quote, the ship's pilots are acquainted with the configuration of the coast. At night they steer the ship by stars and in the daytime by the sun. In dark weather, they look at the south pointing needle. This is why the compass became known as one of the four great inventions of China. Here I should note that the compass aided navigation, but it wasn't responsible for navigation. Many ancient seafaring cultures didn't have the compass, most notably the Polynesians.

And if you remember back to my episode on Polynesian navigators, they were capable of of open ocean navigation without a compass. But nonetheless, having a compass was a huge advantage. With a compass, you didn't necessarily need to see the coast, or the sun, or the stars. This could, if nothing else, prevent you from sailing in circles. How the compass spread beyond China is a bit of a mystery. The period of time between when the navigational compass appears in Chinese literature and when it appears in European literature is actually rather short. The first written mention of the compass in Europe was by the English writer Alexander Neckham, who wrote in the early 13th century, quote, The sailors moreover as they sail over the sea, when in cloudy weather they can no longer

profit by the light of the sun, or when the world is wrapped up in the darkness of shades of night, and they are ignorant to what point of the compass their ship's course is directed, they touch the magnet with a needle, which the needle is whirled around in a circle, until when its motion ceases, its point looks direct to the north. End quote. This description of the compass is shockingly similar to that of Shu Yu less than a century earlier. The other odd thing is that the evidence of the compass appears all the way over in England before it appeared in the Muslim world. By the 12th and 13th centuries, anything which came from China to Europe would have had to have

come through the Islamic Caliphate. So either the compass somehow skipped over the Muslim world, which seems very unlikely, or for whatever reason, it just didn't appear in the writings. When the Islamic world finally received the compass, it was used. not only for navigation, but also for determining the Kibla, which is the direction towards Mecca which was used for prayer. Around this time, the Chinese were still using wet compasses for navigation. They worked, but they had serious limitations. Water sloshed around on a ship, so it was practically hard to use. In Europe, there were several innovations which were made

to the compass. The first was a practical working dry compass. The Chinese dry compass was just a needle on a string. The European dry compass was a freely pivoting needle on a pin that could be balanced and put inside of a glass case. This really isn't too far from how most compasses are built today. The second big innovation was the creation of a wind rose. This is the underlay of a compass that shows the cardinal directions of north, south, east, and west, including the bearings in between. It's often the shape of a star, and this allows for taking bearings in almost any direction. and this eventually evolved into the fleur-de-li, which became the symbol of France and the New Orleans Saints. Finally, for ships, the wooden box that held the needle was placed in a gimbal, which was then placed in another gimbal.

This allowed the compass to remain level, even when the ship was being tossed. There were also European wet compasses that were developed for the purposes of astronomy, which didn't have to move. There were eventually wet navigational compasses built, where the liquid was contained within the box, which provided extra stability to the needle. These European innovations to the compass eventually made their way back to China via Japan when the Europeans began visiting Asia, sort of closing the loop on the compass. One of the things that was required to accurately use a compass was compensating for magnetic declination. Magnetic declination was discovered by the Chinese when they were still using the south-pointing fish. Because the magnetic north pole isn't the same as the geographic north pole, there is usually a difference between where the needle of a compass points and true no. north. This angle difference is known as magnetic declination or magnetic deviation. This difference

changed depending on where you were. The declination in London, for example, would not be the same as it was in Copenhagen. Moreover, because the magnetic poles wander, magnetic declination could change over time. This led to the creation of declination maps that could be used by navigators. In the 1830s, the British launched what they called the Magnetic Crusade, which was a worldwide effort to create a complete map of magnetic declinations. Magnetic compasses have advanced, but they still aren't radically different from the compasses which existed centuries ago. The principles are still fundamentally the same. If you buy a compass today, it'll probably be a magnetic needle or card, floating in a liquid for stability encased in glass or plastic. One innovation used in hand compasses were

sites that allowed for taking more accurate bearings. This was initially for military use, but it also led to the development of a sport called Orienteering. Orienteering began in Sweden in the late 19th century as a competitive military exercise. The first large-scale meet was organized by the Swedish major Ernst Kilander in 1919. The sport caught on in Scandinavia and Eastern Europe and spread around the world from there. Today, Orientering is a cross-between navigation and cross-country racing. It requires both speed and accuracy. There is an Orientering World Cup that's held every year that hosts multiple events across four different disciplines, foot, mountain bike, ski, and trail orientering.

There has been discussion for years about making orientering in Olympic sport, but to date nothing has happened. There is a good chance that you have a compass on the smartphone that you are listening to this very podcast on right now. It isn't a compass with a magnetic needle, however. It uses a computer chip known as a magnetometer, which acts the same as a compass. If you're using an iPhone, there is actually a compass application on it if you haven't used it before, so go check it out. Likewise, many aircraft have a gyroscopic compass that establishes

orientation without the use of magnetism. It can do the exact same thing, but just with a different mechanism. A GPS device cannot actually give you direction. It can only provide location, but it can provide direction, however, if you're moving, as it can just compare the differences between your last two locations. Good old-fashioned magnetic compasses are still in regular use. Geologists have to learn how to use what's called a Brunton compass, which is designed for geology fieldwork, and I remember having to learn to use one when I did geology field mapping one summer. Likewise, they can still be found in ships. I was once able to visit the bridge of an aircraft carrier while it was at sea.

Despite all of the advanced navigational equipment they had at their disposal, they still had a magnetic compass. Despite the easy access we now have to GPS systems and computer maps, learning how to use a paper map and a compass is still a worthwhile skill to have. Having the knowledge is not only useful, but it will make you part of a long tradition that goes back 2,000 years to ancient China. Everything Everywhere Daily is an airwave media podcast. The executive producer is Darcy Adams. The associate producers are Thor Thompson and Peter Bennett. Today's review comes from listener Scott Moffat over at Podcast Republic. He writes, Gary delivers interesting stories and facts about various topics at length that make sure the topic doesn't get boring.

This podcast is absolutely the best of its type that I found. Thanks, Scott. I'm glad you find the show best in breed, and I promise that I will always try to keep it not boring. Remember, if you leave a review or send a boostogram, you too can have it read in the show.