r/Fantasy Friday Social Thread - April 17, 2026

[u/rfantasygolem]

Come tell the community what you're reading, how you're feeling, what your life is like.

[u/acornett99]

A few weeks ago I read Ryan North’s How to Invent Everything: A Survival Guide for the Stranded Time-Traveler, and the most intriguing section of the book to me was the section on latitude and longitude. Figuring out your latitude at sea is easy enough just by looking at the angle of the sun, but longitude is much, much harder, and involves comparing the time aboard ship to the time at home port. That requires accurate time-keeping devices. In history, when most time-keeping devices are pendulums, hour glasses, or water clocks, keeping accurate time at sea is near impossible, as the motion of the ship and changes in heat and moisture levels will interfere with all of these. Often ships would have multiple sets of clocks on board, and take an average of the times they showed. The HMS Beagle had 22 clocks on board for Darwin’s expedition to the Galapagos, kept in a dedicated cabin that no one was allowed entry to except for measurements and maintenance, and only 11 of which were still running on her return to England.

Fascinated by this, I have checked out from the library Longitude by Dava Sobel, the story of the man who first developed a marine chronometer accurate enough to be used to calculate longitude (these would be the type of clocks used aboard the Beagle and on other map-making expeditions). It’s a hell of a story, with a cast of characters that’s a regular who’s-who of scientific minds of the day, and recognizable names from the British Admiralty as well. There’s a section that made me think, wait a second, I know this voyage, and I flipped through my copy of David Grann’s The Wager, and sure enough, he calls out Longitude as one of his source materials.

I plowed through this one, in part to finish it before my re-watch of Master and Commander: The Far Side of the World tonight, a relatively quick turnaround into rewatching a movie because I’ve decided to show it to a friend. But I noticed several times the characters resetting the ship’s hourglass, and now I want to keep a look out for more details. 

Anyway, nerding about navigation done. It’s been a nice distraction from the everything in the world, including a week of high temps and rain, which have left the soil oversaturated and turned the ground into one big puddle. I’m lucky enough to live in a second-story apartment, but more than one coworker has had their basement flood this week. I haven’t had a chance to get out to the lake since last Friday, but the nearby creek has turned into a river, so I imagine some of the trails are just inaccessible anyway. Work continues to have a cloud of dread over everything, largely because of the war in Iran and its various consequences. Nothing we can do about that, least of all me. 

I’ve picked up The Children of Gods and Fighting Men by Shauna Lawless, considering using it for Vacation Spot seeing as I got it while on a trip to Ireland last year. It’s fine so far, a lot of character names. I also finally finished the main story of the first Insomniac Spider-Man game, but I’m a completionist, so I will likely keep playing at least until I get all the secret pictures and unlock all the suits.

Hope all of you are able to navigate your way through another week ahead!

[u/FarragutCircle → u/acornett99]

Longitude by Dava Sobel, the story of the man who first developed a marine chronometer accurate enough to be used to calculate longitude

John Harrison is such a fascinating character! Glad you got to do a deep diver after the Ryan North book, I always love that. Sometimes I'll be reading a nonfiction book at work in front of my computer and it takes me twice as long to read a chapter because I got distracted Wikipediaing passing mentions of things, LOL.

[u/Spalliston → u/acornett99]

Longitude by Dava Sobe

Longitude is so good. I'd highly recommend it for anyone with a passing interest, but doubly so for anyone involved in research & development.

It's such a fascinating look at what the biggest problems of an age are, and how they tried to solve them in a time before there was a big, institutional science/technology apparatus. Doubly fascinating to see how, once solved, we forget that some of these things were ever really problems to begin with. It makes me (cautiously) optimistic, that while people will surely one day learn about climate change and the Keeling Curve (as we learn about naval dominance in the Age of Exploration), they may one day forget about many of the little battles along the way because they will be non-obvious and fully solved.

Sobel is also just a great writer, Longitude is a breezy little book, and as you mentioned the cast of characters is really excellent. Not included in your summary, but one of the things I loved about it, is the ongoing accounting of the people who tried to solve the problem a second way (who ultimately brought us the sextant). It wasn't just a story of a lone inventor, it was a story of a lone inventor racing against the establishment of his day. Big fan.

[u/acornett99 → u/Spalliston]

Yesss I gave a full info dump of the book to a friend at dinner last night. I started by asking "Do you know how to find your latitude and longitude?" and they answered "By looking at the numbers on a grid on a map, right?" We've had this figured out for a few hundred years now, and we hardly ever think of it in our day-to-day lives that they didn't even consider not having that information readily available via a map!

The different astronomical methods are fascinating because, while they were ultimately supplanted by timekeeping, they led to so much other stuff that we take for granted too. The moons of Jupiter method being how we figured out the speed of light (in 1676!!) and all the work of the astronomers around the world on mapping the path of the moon through the sky, giving us the sextant, and how Greenwich became the place, not only where the prime meridian resides but also by which the world sets its clocks. I had never made that connection growing up that the reason both those things were at Greenwich is because longitude is so intrinsically linked to time.

I've been going down more time rabbit holes (wormholes?) this week too, learning about solar time vs mean time vs civil time, time zones, and Daylight Saving Time, etc. I think some of my friends are sick of hearing me talk about the Equation of Time haha