Passage of the sun determines day, night, and time. Trains gave us time zones. Image: “Sun Animation” by Sfls4309pks and Trekky0623/The Flat Earth Society. Creative Commons 4.0.

As the sun rises and sets, the resulting diurnal rhythm is what we call time. Before the world became connected through high speed transport, local towns set their own clocks. Noon was determined by the high point of sun in the sky: so, noon in Boston might be a bit different from noon in Baltimore, and certainly different from noon in Boise. There were 144 varied “time zones” in North America in the 1880s.

US Transcontinental Railroad used little papers called “flimsies” to alert track workers of coming trains. Time zones soon followed. Image: Transcontinental workers by photographer Andrew Russell, 1869. Public Domain.

Trains changed the world in many ways including time. When the US built the Transcontinental Railroad, collisions on tracks were avoided by runners sent ahead with reports of trains arriving. Using lightweight paper, warnings were called “flimsies” – not too reassuring when the safety of passengers was at stake.

Early rail tracks were laid to haul coal from mines. Image: “Mine Cart” by photographer LoKiLeCh from Berlin Technikmuseum Holzbahn. 2010. Creative Commons 3.0

British rail, emerging from wooden (and then iron) tracks making it easier to convey coal from mines to waiting barges, may have begun the rail era, but it took until 1847 for British rail companies to adopt one time schema across the rail system. It was called “Railway Time.”

Canadian Pacific Railway built snow tunnels and snow galleries (pictured above) to keep working through winter. Canadian Pacific Surveyor Sanford Fleming introduced the idea of time zones, and changed the world. Image: “Snow Gallery at Crested Peak,” by Carleton Watkins, 1868. Public Domain.

Canadian rail surveyor Sanford Fleming, who worked on the development of the Canadian Pacific Railway, that brought the idea of time zones to the world. Fleming proposed four time zones for North America: Eastern, Central, Mountain, and Pacific. The idea changed a continent and then the world.

Concept of a prime meridian predates the 18 November 1883 International Prime Meridian Conference that chose Greenwich as the center of the time cycle. Here, a 1595 illustration by Gerardus Mercator. Courtesy Library of Congress. Public Domain.

On 18 November 1883, Fleming’s system brought the world together for the International Prime Meridian Conference in Washington DC in one of the most important global agreements. Greenwich Meridian was chosen as the “zero” center of longitude, and set the sounding note upon which the harmony of world time became based. Can we agree upon climate goals and timeline, now?

“Analog Clock Animation” by Jahobr. Public Domain.

Noon, 18 November 1883 became known by a special name. Why? At noon that day, all rail stations set their clocks according to the new Prime Meridian system adopted. But because most town clocks and sundials at the stations may have already passed noon, or were about to based on the overhead sun, those systems also hit their mark. So, 18 November 1883 became known in history as the “Day of Two Noons.”

Swatch introduced Internet time – a day has 1000 beats and we all keep that beat at the same time. Image: Swatch Blancpain 0319 by photographer Rama. Creative Commons 2.0.

While the world still works on Fleming’s idea, modern communication systems – a form of transport – like the Internet sparked a new time concept. Swatch watch maker proposed each day be portioned by “beats” as the rhythm of time and perhaps a certain bow to musical time signatures. Internet time has 1000 beats: each lasts 1 minute and 26.4 seconds. Its central meridian was located in Swatch’s office in Biel, Switzerland. They called it BMT (Biel Mean Time). Going beyond Fleming’s view of the world, BMT or Internet time does not have zones: we’re all online simultaneously – on the same beat.

Doomsday Clock, as portrayed in the graphic novel “Watchmen.” Illustration by Kigsz, 2012. Creative Commons 3.0.

Coordinated Universal Time (UTC) has lately been the new standard, coordinating time zones with the Earth’s rotation. International Atomic Time (TAI) combines the readings of 400 atomic clocks. Universal Time (UT1) is astronomical time based on the Earth’s rotation: it’s related to the International Meridian Conference’s system, and remains the standard. Another clock we all might watch carefully (see above) is the Doomsday Clock.

As the world meets in Baku for COP29, can we agree on goals? It’s about time. Image: “Baku at noon with vertical shadows indicating precise time of noon,” by Alexey Bogolyubov, 1861. Public Domain.

If the world can agree on time zones, can we hope that we will now find a way to agree upon climate goals and justice? It’s about time.

Brooke, K. Lusk. “Day of Two Noons.” 18 November 2022. https://blogs.umb.edu/buildingtheworld/2022/11/18/transport-day-of-two-noons/

Brown, Lynn. “How railroads inspired the creation of time zones.” 18 November 2024. BBC. https://www.bbc.com/travel/article/20241115-how-railroads-inspired-the-creation-of-time-zones

Bulletin of the Atomic Scientists. “2024 Doomsday Clock Announcement,” 23 January 2024. https://thebulletin.org/doomsday-clock/

COP29. https://cop29.az/en/home

Davidson, Frank P. and K. Lusk Brooke. “The Transcontinental Railroad,” pages 205-218; and “The Canadian Pacific Railway,” pages  253-287. Building the World. Greenwood, 2006.

International Prime Meridian Conference. For the founding document: https://greenwichmeantime.com

New York Times. “Turning Back the Hands: A Quiet Change to the Standard Time.” 18 November 1883. Digital reproduction of text: http://historymatters.gmu.edu/d/5748

Terrell, Ellen. “The Day of Two Noons.” January 2021. Library of Congress. https://guides.loc.gov/this-month-in-business-history/november/day-of-two-noons

Building the World Blog by Kathleen Lusk Brooke and Zoe G. Quinn is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 U