(May) maybe if I ask your dad and mom
Neil Sedaka, “I Love My Calendar Girl”
(June) they’ll let me take you to the Junior Prom
(July) like a firecracker all aglow
(August) when you’re on the beach you steal the show
Yeah, yeah, my heart’s in a whirl
I love, I love, I love my little calendar girl
We take the division of time for granted. How many minutes left on the test? What time do I get off? Is the next holiday on Monday, so I can have a three-day weekend? Some people even wear wrist devices which describe those divisions, linked to their health data, like their heart rate and whether they sleep. However did we manage before a wristwatch could describe our sleep?
The ancient people had to invent all those divisions from scratch. They did it repeatedly, across multiple cultures, using varying tracking systems. Their lives depended on observations–the rise of the river waters, the start of the dry season, the first bite of frost. I was well into middle age before I noticed how far north the sun set in the west in the summer vs. the winter. I think it was because I’d finally lived in one place for more than a decade. I bet even the Neanderthals figured that out before I did, since their lives depended on such things.
Today’s topic is the Calendar. How could they mark time, before writing was even invented? How did different societies integrate math with time? Were there different versions of calendars? Where did they stand on ending Daylight Savings Time?
As always, I want to cover three topics:
- A core definition of the “thing”
- Where and when it happened first “around the world”
- How it influenced human development
Hope and the Spring Thaw
Calendars serve multiple functions. In original form, calendars were a translation of observed natural events. The sun arcs across the sky every day. Where the sun starts and ends its daily journey also changes over the year, matching changes in the weather and the plants around us. At night, the moon changes its visible shape and pathway. Even if early humans didn’t have the science to understand the motion of planetary bodies, they would have wanted a system that would describe these changes.
Before there were written signs, there was still knowledge and language. Even before before the Mayan long count, the Chinese lunar solar calendar, and the Sumerian calendar of Nippur, people could conceive of important dates. The first thaw of the river. The big rains. When the sun is highest in the sky. There were other ways of communication, too, not people making sounds to each other but seeing natural markers like trees and hills. These could indicate the dates as well: when the sun touches the last big stone.
Calendars, whether written, drawn, spoken, or fashioned out of natural objects, were ways of measuring and recording. The first thaw of the river comes every so often; how do we divide up the time between then and now? The ancients surely noticed that time on Earth moves in only one direction. A calendar implies a past, a history. And a calendar means a future, a predictable estimation of what might happen in the next thaw. When is a guide post for tomorrow. When means hope.
Was Stonehenge a Calendar?
Calendars have been built around large objects in England, Turkey, and Peru, just to name three examples. Maybe you visited Stonehenge in years past, when they used to let people touch the stones. Too many people caused damage to the monuments, so they no longer let you get close. I saw it from far away, but knowing that the bluestones now on the Salisbury Plain came from faraway Wales and were transported for decades over rolled logs, is mind-boggling. The pit design of Stonehenge was begun around 3000 BCE, but took centuries to complete because–giant stones, far away, no trailer trucks or roads. It’s designed, of course, so that the sun travels a specific path across the stone faces, striking certain key stones, just so, on the solstices.
There are other, less well-known circles, all over the world. Göbekli Tepe, a 10,000 year old site in southeastern Turkey, also has a circle of megalithic arranged stone pillars, not as large as the Welsh bluestones, but large enough to be seen from far away. Göbekli Tepe was a settlement for people, though, not just (apparently) a site for religious rituals and timekeeping. The pillars have carvings as do many of the walls.
Scientists have studied the carvings for decades, and many argue that they display sophisticated understanding of time and natural phenomenon. One set of carvings that sported a row of Vs is believed to be a calendar because there are 365, grouped in month-like intervals. That would make it the world’s oldest. Other carvings–squiggles, dots and animals–might represent constellations, and one archaeologist believes that they reflect the precession of the equinoxes (didn’t I just write about that?). If the Neolithic Turks understood the precession, it would be a sophisticated, long-range astronomical observation indeed!
Not to be outdone, the ancient Peruvians–long before the Incas built Machu Picchu–constructed their own “linear” calendar. Thirteen stone towers were built along a hillside, referred to as Chanquillo, observable by two other towers on an east-west parallel. The ruins had been a tourist site for decades, but it wasn’t until 2007 that scientists noticed that from the east-west observation towers, the thirteen “teeth” functioned as “landscape timekeeping.” The sun rises above a tooth on one end on the winter solstice and on the other end on the summer solstice.
Are all of these calendars? Chanquillo’s construction makes little sense unless it’s meant to mark time. People lived at Göbekli Tepe. What they carved on the wall could have been functional as timekeeping as well as creative and spiritual.
Of the three, Stonehenge seems the most indirect example of a calendar. It was clearly used for both burial purposes (cremation, barrows) and religious ceremonies. But would you really spend 1500 years dragging giant stones from Wales just so you could know when June is coming? Smaller, more practical structures may also have functioned which didn’t last for centuries. I keep visualizing the Celtic priest–Druid, Merlin, Beaker People, Neolithic agrarians, whatever and whoever the dudes were–the priest raises his staff like Gandalf: Behold! It’s Tuesday! Seems more likely to me that Stonehenge was crafted as a giant monument dedicated to the gods formed in a shape that used natural time-based phenomena for effect rather than the reverse.
How the Sumerians Invented the Calendar, the Daily Beats of Time, and the Circle
Meanwhile, as the Neolithic farmers were dragging those stones over hill and dale in southern England, the folks at the Fertile Crescent were inventing the circle. That is, the Sumerians invented the 360-degree circle and linked it to timekeeping. This integrated view shows how they connected multi-year calendars, annual calendars, geometry, astronomy, and distance measurements. The Sumerians coordinated their mathematical system around Base 60, and it influenced everything.
Why Base 60? First, there are almost 360 days in a year. Even if that’s not exact, they could start with 12 30-day months, then adjust a little. We do that now with Leap Years. The second reason to use 60 and 360 is that they’re handy mathematically. Because 60 is divisible by 1, 2, 3, 4, 5, 6, 10, 12, and 15, it creates very useful fractions. You don’t need a calculator! Thus, if you create your time measurement system around 60×6=360, naturally the divisions within the day could be either 12 or 24, further subdivided by 60. That’s where our minutes and seconds come from.
Also, since timekeeping was understood in relation to the movement of the sun and other heavenly bodies, the Babylonians linked the “circuit” of the year to the circle. Hence, the circle was also defined as 12 slices of 30 degrees each, or 360 degrees.
You Get a Calendar! I Get a Calendar!
The Egyptians took it a step further by using multiple calendars: three different ones. One was built around agriculture, perhaps the most important knowledge needed since irrigation based on the flooding of the Nile was how you could feed a million people. The second, lunar-based calendar was for the priests and determined which day required which offering. Kind of like when medieval Christianity based days on the Saints, to avoid having to use those pagan complex mathematics. Lastly, though, the Egyptians also had a civic calendar to run the large and expanding kingdom. Whenever a new territory was conquered, those folks were put under the Egyptian civil solar calendar, which had the political benefit of unifying the kingdom.
This is similar to how Islam uses the calendar. Because the Islamic calendar is lunar, the holiday of Ramadan shifts throughout the year, but every Muslim around the globe observes Ramadan at the same time. The calendar acts to unify the culture regardless of location.
The Chinese Zhou dynasty, one of the earliest, used a lunisolar approach, and it was complicated. After the end of Zhou, during the Warring States period, multiple regions used their own version, which doesn’t sound given “Warring States.” The Han dynasty, an ancient civilization that also developed sophisticated mathematics, determined the annual calendar to have 365+385⁄1539 days, fairly close to the Gregorian calendar we use today.
The Long Count and the Calendar Round
The Mayans, whose civilization began to flourish around 1100 BCE, took two separate approaches. They had a “circular” annual calendar, or calendar round, which the Aztecs later adopted. This calendar was of practical use for determining where the day stood during the year, when the waters would rise, when the sun was at its height, and so on. But the Mayans had a second calendar, a 260-day calendar, which they used for the Long Count.
The Long Count calendar was constructed around 18 and 20–the Mayans used base 20–and depicted time in a linear fashion. After years of study, scholars working backward think that the count began August 11, 3114 BCE, although they disagree on the purpose of that date. The Mayans used the Long Count calendar for religious observation, but it was a calendar both linear and cyclic. It would repeat itself after 52 years, re-synching the 260-days with the 365-day annual calendar.
The choice of 260 days was not arbitrary. Scholars note that the Mayans, living close to the equator, were able to see the sun at zenith twice a year and were more influenced by that phenomenon than the equinoxes. The idea of the Long Count combined the idea of cycles, already observed annually, with linear history. The Mayans could describe what day something happened in their history as well as predicting when the next count would happen. It was a mistaken notion that the Mayans thought the world would end on December 21, 2012. They believed that the Long Count would click from one cycle to the next, from 12.9.9.9.9 over 13.0.0.0.0. The next cycle (14.0.0.0.0.) will begin on March 26, 2407. That’s what it was called Long, but many of the ancient cultures thought in terms of centuries, not minutes.
For much of human history, these calendars integrated spiritual and practical functions. Only relatively recently, the last few hundred years, has time been perceived as having a purpose independent of nature or deities. Even that still remains linked to ancient practice. After all Spring Break for many schools is linked to Easter, which happens the first Sunday after the full moon after the vernal equinox. Way to combine modern logistics with both Christian and pagan traditions! They gave offerings at the ancient spiritual sites to ask the gods for a change in the weather, to dream of a better harvest. Maybe high-tech wristwatches which tell time, measure a heartbeat, and monitor sleep will relink us to the ancient practices. Well played, AppleWatch…