Calendars are a measure of time and tell what the date is, like the year, month, and  the day. Clocks are also a measure of time, but they are a little different from calendars.  Instead of telling the date, it tells what hour, minute, or second it is. They are both great ways of telling time.

History of Time

The history of time started 4000-5000 years ago.  The first people in the world were hunters and gatherers.  When they noticed the rising and the setting of the sun, they also noticed that it occurred over and over again.
 
Soon, they started planning activities depending on nature’s changes.  They learned to pick and store berries and nuts before winter came, they learned to follow migrating animals with the seasons, and they also learned that the changing seasons told the time of year.

Julian Calendar

In 46 B.C, the lunar calendar had a lot of mistakes.  It was the 1st Roman calendar and it had been borrowed from the Greek Lunar calendar.  It had 28 days in each month and there were 10 months in one year.  The months were called Marius, April, Maius, Junius, Quintilis, Sextilis, September, October, November, and December.  It only had 280 days, 85 days too few.
 
Numa Pompilis made two new  months, Januarius and Februarius, for a total of 12 months, but the calendar still lost pace with the seasons.  When it was winter, the calendar said that it was fall, and when it was summer, the calendar said that it was spring.  That was a big problem!  There were 12x28 or 336 days in the year, 29 short of 365.  Every year, the calendar slid backwards almost a month. 

In 45 B.C, Julius Caesar fixed that problem.  He ordered the lunar calendar to be replaced with the solar calendar.  Then, the calendar would have had 365 days.
 
Julius Caesar’s calendar began in January and had 12 months.  Julius made one of the months July, and another month August, naming the months after himself and Augustus Caesar.  April, June, August, October, and December had 30 days in it.  January, March, May, July, September, and November had 31 days.  February had 29 or 30 days.  Every three years, they added one day to February, over all, this added 85 days to the original ten month lunar calendar.
 
In 27 B.C, Augustus Caesar ( Julius’ son) was the emperor and the ruler of Rome.  At that time, the extra day in February was made every three years instead of four, so a correction was needed.  He corrected the mistake by making July 30 days and August 31 days.  He also took away a day from February to add it to August.  That means February got 28 days, instead of 29.  He changed September and November to 30 days and added one day to October and December.

Christian Calendar

In 525 A.D, someone asked Dionysus Exxius (who was a mathematician and astronomer) to have Easter be on the same day all over the world.  Dionysus calculated when he thought Jesus was born.  The date of that was the beginning of the Christian calendar.  In the Christian calendar, the year 1 B.C was before the year A.D 1.

Gregorian Calendar

The calendar that Julius Caesar invented was called the Julian calendar.  It gained about one day every 134 years.  Europe used the Julian calendar for 1,500 years, so by that time, the Julian calendar resulted in an eleven day mistake.  By the year 1,582, Easter was celebrated at the wrong time.  It was celebrated earlier and earlier.

The Gregorian calendar is the newest calendar in the world.  It’s the calendar that we use today and it’s the most accurate except for the Mayan calendar which is much more complicated.
 
In 1582 A.D, Pope Gregory invented the Gregorian calendar.  He ordered his mathematician and astronomer named Clavius to fix all the problems in the Julian calendar.  He made the leap year rule.  He also took out 10 days from that one year.  One day, it was Thursday, October 4, 1582 and the next day, it was Friday, October 15, 1582.  The only difference between the true solar year and the Gregorian calendar is 26 seconds.
 
The Catholic countries and other countries didn’t want to change to the Gregorian calendar because they were so used to the Julian calendar.  One country that didn’t want to change to the Gregorian calendar was England, because they already had a calendar called the English calendar.  In 1752, England finally switched to the Gregorian calendar.
 
Other countries that switched to the Gregorian calendar after England were Japan (1873), China (1912), Russia (1918), and Greece (1924).  In these countries, the Gregorian calendars were used only for government and business, and the traditional calendars were still used.
 
China’s traditional calendar has 12 animals that represent the year.  One year, there’s one animal, and another year, there’s another animal.  After 12 years, the calendar repeats itself.  The animals are: Rat, Ox, Tiger, Hare, Dragon, Serpent, Horse, Ram, Monkey, Rooster, Dog, and Boar.
 
In India, there are more than 30 calendars.  The government tried changing that, but there are still a lot of calendars.  The Buddhists, Hindus, and Jains still use their own calendars.
 
Some of the world wants a new calendar without any religious ties.  They want that because not everyone is Christian and the Gregorian calendar is a Christian calendar.

Maya Calendar

The ancient central American nations, like the Aztecs and the Toltec, adopted the Maya calendar.  The Maya calendar used  three dating systems called the LongCount, the Tzolkin which means divine calendar , and the Haab, which means civil calendar.  Out of the three dating systems, the Habb has a direct relationship with the length of the year. It’s similar to the Julian Day Number.

The Long Count dating system.  It represents the number of days since the beginning of the Mayan era. The basic unit is the kin, which means day.

The Tzolkin dating system is a mix of two lengths.  Our calendar(Gregorian Calendar) uses one week which has seven days, but the Mayan calendar used two lengths of the week, the week has 13 days, and the days are numbered from 1-13.  There’s also a week of twenty days, in which the names of the days are, 0. Ahau, 1. Imix, 2. Ik, 3. Akbal, 4. Kan, 5. Chicchan, 6. Cimi, 7. Manik, 8. Lamat, 9. Muluc, 10. Oc, 11. Chuen, 12. Eb, 13. Ben, 14. Ix, 15. Men, 16. Cib, 17. Caban, 18. Etznab, and 19. Caunac.

Hebrew Calendar

The Hebrew calendar is the official calendar of Israel and Jews.  It started in 3,760 B.C based on the Gregorian calendar.  There are about 12 or 13 months and 7 days in a week.  The last day of the week is called Sabbath, which means Saturday.

Islamic Calendar

The Islamic calendar is a traditional calendar that is used for both civil and religious purposes.  It dates from Higarae and based on the Gregorian calendar, that’s the year 622.  Based on the Muslim calendar, that’s AH1.  AH means Anno Higarae.

Calendars are one way of telling time but clocks are another way.  Calendars tell what day, week, month, or year it is.  Clocks tell the hours, minutes, and seconds.

Thousands of years ago, people kept time by measuring shadows that were made by the sun.
 
The shadows shortened around noon and lengthened in the evening.  The length of the sun’s shadow told the time of the day.

Hourglasses

An hourglass is a device to measure time.  It has two bulbs, one on top of the other, and they are connected by a skinny tube.  One of the bulbs is filled with sand, and when you flip the hourglass so the bulb with the sand is on top of the other bulb, the sand will flow to the bottom bulb, and when all the sand flows into the bottom bulb, that’s a certain time period.  The hourglass doesn’t have to be an hour.  The volume of sand, the and the angles of the bulbs, the width of the tube, and the quality of the sand affect the time period of the hour glass.

The hour glass is also called a sandglass, or sand timer.

Sundials

A sundial only tells the time when the sun is shining.  A stick/pointer called a gnomon casts a shadow onto a flat surface marked by the hour, so that’s how sundials show time.
   
 The Egyptians, Chinese, and Sumerians used sundials.
 
All sundials aren’t big.  In fact, some of them are even small enough to fit in a pocket.
 
Water Clocks

In 325 B.C, water clocks were invented.  The country that used water clocks was Egypt.  In a water clock, there are two containers.  One of the containers is diagonally under the other container and there are marks on the bottom container.  Each mark is one hour.
 
There’s water in the top container, which drips into the bottom container.  When the water in the bottom container reaches a mark, that’s one hour.  When the water reaches the mark above the first mark, that’s two hours, and so on.

Mechanical Clocks

Mechanical clocks began in Europe and were set in clock towers.  In the clock, there are heavy weights tied to cords that are wound on a spool.  When the cords unwind, they turn a set of gears, which move the hands on the clock.

Pendulum Clocks

Around the 1600’s, pendulum clocks were invented.  For the pendulum clock to keep a steady beat, it has to be on a perfectly flat surface.  The shorter the pendulum, the faster the beat.  The longer the pendulum, the slower the beat.

Mechanical Clocks

Mechanical clocks began in Europe and were set in clock towers.  In the clock, there are heavy weights tied to cords that are wound on a spool.  When the cords unwind, they turn a set of gears, which move the hands on the clock.

The Time Zones

About 100 years ago, the 24 time zones around the world were made.  The time zones are centered on the Prime Meridian.
 
The time zones were made because, as Earth rotates, different places have different times for sunrise, day, sunset, and night.
 
The time zones start at zone zero (the Prime Meridian) in Greenwich, England.  The time zones located to the East of Greenwich are later.  The time zones to the West of Greenwich are earlier.  All the time zones are one hour apart.  All clocks keep about the same time in the same time zone.
 
In a small country, city, state, or region, there’s only one time zone, so the time is the same.  If it’s a big country, there are more time zones.  From Washington to Maine or Florida, there are three time zones.

The New Millennium

The new millennium is very short in history. Scientists believe Earth has existed for 4.5 billion years and the universe has existed for 12 billion years, so Earth has existed for about 4.5 million millennia.  Since the Gregorian calendar starts with the Death of Christ as the year 0, year 2000 A.D was the end of the 2nd millennium.  The year 2006 is just 6 years into the 3rd millennium.
 
The new millennium was in the year 2000 and it is very important to Christians because it’s an anniversary of Jesus’ birth.
 
We don’t know what time is but we’ve mastered it in our daily lives.  Calendars and clocks are not perfect but they are good enough.  Clocks and calendars are still improving.  Lasers and mercury atoms might even give a new generation of more accurate clocks.  The world could even make a new calendar system.

Who I Interviewed And What I Learned I did an interview of Montgomery Walker on December 12, 2005. I interviewed him at the Selah Library and he was an excellent interview because he is a history and geography instructor at YVCC.  He said he’s been involved with history for 20 years and has been a paid historian for 7 years.  He said that he is currently involved with calendar history because it comes up in his history and geography classes.     He got interested in history because it’s fun to learn about things in the past and learning about the people from the past. He said it makes him feel like he’s going to another country. The thing he enjoys about calendars and their history is that it’s something that people don’t think about but yet it’s very complex and very old.     He told me the history of the calendar in a very simple version and he said that the Egyptians were the first people to invent a calendar that was based around the movement of the sun.  They replaced their calendar in around 2772 B.C. When the Romans conquered Egypt around 45 B.C, they noticed that the Egyptian calendar was better than the Roman calendar, so they adopted it. They also noticed that they were celebrating Easter earlier and earlier, so pretty soon it would be in the winter.   In 1500 B.C, Pope Gregory XIII had some mathematicians who figured out how to fix that problem and he invented the Gregorian calendar. That’s the calendar that we use today.  He said that calendars started about 13,000 years ago and that the first written calendar started about 5,000 years ago.     People made up calendar systems by observing the movement of the moon and the position of the sun.  People a long time ago were always outside so that’s how they started noticing the cycle of the moon.     The new study or field of calendars is looking at ancient calendars and debating over their intention.  Some people who live in different countries don’t use the Gregorian calendar but they use the Islamic, Hebrew, Chinese, and the Mayan calendar.     Pope Gregory didn’t really know how to make a new calendar but the mathematicians who were working for him knew people were trying to fix the Julian calendar so the mathematicians fixed it.     Montgomery Walker thinks that if there was no such thing as calendars, the world would be disorganized, free flowing and he thinks that we would be outside looking at the moon more often.  He also thinks that organized people would be chaotic.  He thinks that there will not be a new type of calendar because people are used to the Gregorian calendar and the Gregorian calendar is very accurate.

Bibliography “A Walk Through Time”.  http://physics.nist.gov/GenInt/Time/ancient.html Cockroft, Irene.  “Calendar” World Book Millennium.  2000. Pp.29-31 "History of the Calendar." Infoplease. © 2000–2006 Pearson Education, publishing as Infoplease. 16 Mar. 2006 http://www.infoplease.com/ipa/A0002061.html Maestro, Betsy.  “The Story Of Clocks And Calendars”.  New York.  Lothrop, Lee and Shepard books.  1999.  4-19, 24-41 Walker, Montgomery.  Personal interview. December 12, 2005

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