The Sunny Side of Almanacs

After the Chinese god of creation Pangu opened up the heavens, and the universe formed out of chaos, the concept of time and years had to wait countless ages to form in the minds of men. The early Chinese "observed the phenomena of nature to know what time it was." Famous meteorology expert Feng Peng-nien points out that the ancient Chinese observed sunrise and sunset and they called the time between one sunrise and the next a "sun," which is the Chinese word for day. Then they saw that the shape of the moon changed, and so they called the time between one full moon and the next a "moon" (or month). This was not difficult. Every ancient nation all over the world had a similar beginning, and they all scheduled their lives around a lunar calendar. But days and months are short periods of time. How could they be extended to a year? This was really a form of art.

In the Hsia dynasty more than 4000 years ago, the early Chinese used sundials to observe the shadow of the sun. They discovered that on a certain day in the summer, the shadow of the sun was the shortest and the daylight was the longest. The ancient people described it as "the time when the sun grows." This day was the summer solstice. And on a certain day in winter, the shadow of the sun was the longest and the daylight the shortest, "the time when the moon grows." This was the winter solstice.

The summer and winter solstices are actually due to the earth's spinning one revolution around the sun. As their relative locations change, so does the angle at which the sun's rays strike the earth.The span of the earth's surface that the sun directly strikes is very small; but it moves between the Tropics of Cancer and Capricorn, year in and year out. On the Summer Solstice, the sun shines directly on the Tropic of Cancer. At this time the northern hemisphere receives the greatest sunshine and the climate is at its hottest. On the winter solstice, sunlight strikes directly all the way down in the southern hemisphere, and the northern hemisphere is at its coldest.

To tell the time in harmony with the rhythm of the seasons, one must calculate by the sun. Furthermore, the shadow of the sun is at its longest on the winter solstice, and it is useful for checking the sundial to see if it is working correctly. Therefore, the early Chinese called the time between one winter solstice and the next a "Latitudinal Year."

Forget the dates, remember the Terms

The length of a month is based on the moon. It takes 29 1/2 days for the moon to complete all its phases. A year, based on the sun, takes 365 1/4 days. And the cold-hearted powers-that-be are unconcerned about the convenience of mere people in regard to the motion of the sun and the moon. If you use the lunar calendar and calculate a year as twelve months, it is 11 days shorter than the time it takes for the earth to orbit once around the sun. For example, the winter solstice appeared in the 11th month of the lunar calendar one year, and after ten years, it surprisingly appeared in the 3rd month. If no one came up with a good method, the world would fall into chaos after a while.

This was no paranoid alarm from Chicken Little. The Roman calendar in the West was originally based on the moon. But they didn't calculate the days accurately. It engendered such laughable blunders as having June arrive while heavy snow was still falling. In a huff, Julius Caesar abandoned the lunar calendar and followed the sun. This is why the solar calendar prevails in today's world.

The Chinese ancestors were more inspired at mathematics. They invented a "leap month," a system which inserted an extra month once every three years to rectify the disparity between the solar and lunar calendars. This system was made even more precise when they changed the ratio to seven months for every 19 years. Nevertheless, putting in "leap months" could only coordinate the two calendars; it could not make the dates on the lunar calendar accurately reflect the real location of the sun. Neither could it inform the farmers what date in any given year to plant their crops. How could they resolve this dilemma? The 24 solar terms rose up in response to popular demand. To cultivate crops, the farmers didn't have to look at the dates, but merely had to remember the Solar Terms. How simple and accessible at a single glance!