Where 2.0: History's best geohacks
Chris Spurgeon
I’m not a professional historian but I’m a science history junkie. Come back time and time again to the geo-scientists who are unique to this great mix, politics, maths, navigation, others…
Will be talking about 3 hacks that are particularly cool.
Hack #1. Squaring the circle - Gerald de Cremere - changed his name to Gerardus Mercator. He was an extraordinary artist, made highly detailed maps, one of the best engravers. Also superb if not the best globe maker on earth at the time.
Washington Irving invented “historical fiction” he invented this story that Columbus discovered that the world was round.
Back to mercator - lived in a volatile town, lived around Netherlands/Belgium. Martin Luther came along and challenged the Christian church. Mercator also did the same and was tossed into prison for being a heretic. He literally didn’t know if he was going to be tortured or killed. Fortunately after 7 years he was released from prison. His teachers vouched for him. He learned that to “Always stay on good terms with your thesis advisor”. He returned to his profession of map making, dealt with the issue that cartographers have found there’s an issue that the earth is spherical and maps are usual flat. They found it’s basically impossible to combine the two without distortion. These things are called projections. Mercator invented “the mercator projection”. All projections have imperfections. Mercator’s is that things really stretch out as you get to the top of a map. Why was this so important? What was it like to sail back then? Could you tell direction? Yes - compasses. Could you tell how far you’d gone? Kinda - measure your wake. Could you measure your latitude? Absolutely, by measuring the angle of the sun/stars. Could you measure longitude? No, noone could figure out how. Given you can measure distance and latitude, he used these tools to design a map.
Let’s pretend we’re sailing from London to New York. You start North West and end up South West. If you plot it on a mercator map, it’s a weird curve. If you were sailing you’d need to modify your compass direction and you’d need to know your longitude to do that. What if you draw a line that’s always the same compass bearing, but perhaps isn’t the shortest direction. If you plot that on a mercator map, it’s a straight line. That’s very important for navigation. The calculations to figure out lon/lat to position on a map is essentially very simple. That’s why it’s so often used right now.
Hack #2. Does anyone really know what time it is?
People were literally dying to find out what their longitude is. People were dying as ships crashed because they didn’t know accurately where they were. The British government established a prize to solve this problem. They would give someone 20,000 pounds to define longitude within a single degree. Lots of crazy people came out of the woodwork. One guy said take a litter of puppies, put one puppy on the shore, and one on the boat, if you burn one at noon the other will yelp. If you knew the time accurately between England and the ship you could measure the longitude by looking at the sun. John Harrison was completely aware of this so figured out all he had to do was make an accurate clock. That’s really difficult, especially at sea, pendulum clock won’t work as it’ll swing about. Spring clock will get hot and cool.
He built this clock - H1 - exists at the Grenwich museum. He built the clock over severallyears then went to the Longitude board and asked for a sea trial. They sailed from England to Lisbon using the clock to work out their direction. Worked well but they decided this wasn’t a big enough test. This pissed him off. He improved it a bit, made a few more versions, 4th version of the clock, 25 years later - the H4 - this is a masterpiece, bit bigger than a pocket watch. Goes back to the board and says “lets try again”. They sailed with the clock in a box and can only be wound when it’s in a box to make sure they didn’t cheat. Sailed to Jamaica, Bermude and back. The error was about 1/3 of a degree. “You ever tried being paid by the government?” They make him sail it again so this time his son sails to Barbados. The clock loses a 1/5th of a second per-day. He sails back, this time the longitude board says he has to do it again. By now he’s really getting pissed, but King George Vth hears the story and decides he has to get his money, which he does shortly before he dies.
Takeaways:
- You can look at the world in a new way, the way Mercator did, invent a new way of seeing.
- Increased precision, increased accuracy changes the way we work. [JMCK: sorry, didn’t quite get this]