A sundial. Photo: Gurk Priory, Austria / Wikimedia Commons.
Travelling through time
Catherine Henderson writes about understanding time and making your own sundial
In my hall there is a grandfather clock. On the clock face is a painting of a woman resting her chin on her hand. I think, perhaps, she is day-dreaming.
I used to watch my grandfather, and later my father, wind the clock each night before he went to bed. He unlocked the front of the clock with a tiny key, which was tied to a piece of cork so that it wouldn’t get lost. Then he gently pulled up the lead weight inside on a long, rattly chain. All night and all day the weight would slowly sink down the long body of the clock, the hands would turn and, each hour, a bell would chime.
Now it is my turn to open up the clock each night and pull up the weight, so that the clock keeps ticking, like the heartbeat of the house. The clock has travelled through time from where it stood in my grandparents’ house to where it stands now, in my hall.
I have always loved this clock. But I don’t particularly like the idea of clocks. Sometimes it feels as if they rule our lives. It hasn’t always been like that.
Two hundred years ago most people didn’t have clocks and watches. They could tell what time of day it was by looking at a sundial. A stick, called a gnomon, in the centre of the dial casts a shadow that moves across the marks on the dial to show you the time of day. (This isn’t much good at night, of course, but most people would be asleep then, as electric lights hadn’t been invented and candles and other forms of lighting were expensive, so people just went to bed.)
You can make your own sundial by pressing a stick in the ground, somewhere the sun can reach all day. Tilt the stick slightly so it is pointing north. Every hour, place a shell or pebble where the shadow of the stick falls. By the end of the day you should have a curved line of these around the stick, marking the hours between sunrise and sunset.
Telling the time by the sun works very well, except that the time is slightly different in different parts of the country. If you live in the east of the country the sun rises earlier than if you live in the west. For example, Dover, in the south-east, is twenty-five minutes ahead of Falmouth, in the south-west.
When people started travelling by train this caused chaos, because the railway timetables just didn’t work. If you caught the 10 o’clock train from Bristol, it was already 10 past 10 in London. So people decided all the clocks had to be set to London time, as they are today.
If we travel back another 2,000 or so years, people in Britain understood time very differently. Instead of thinking, as we do, of one year leading on to the next, and time moving forwards, our ancestors thought of time more like a wheel, turning through the different seasons of the year and always coming back to the starting point. So, each year followed the same pattern: you planted and harvested your crops, your animals gave birth, and you stored food to get through the winter. Each season there was a great fire festival, when everyone would eat and drink, sing, and dress up and tell stories. Actually, that never quite died out. We still have a fire festival very close to the day our ancestors celebrated their new year, which was 31 October. Ours is a few days later.
One last bit of time travel. Do you ever look out of the window, or go outside on a clear night, and see the stars? The distance we are away from them is so great that astronomers measure it in ‘light years’. A light year is the distance a beam of light travels in one year: six trillion miles!
The picture below, taken through a telescope, is of the Andromeda galaxy, the nearest to our own, which we call the Milky Way. You can see it without a telescope as a faint oval blur in the sky. The light we are seeing when we look up at this particular swirling mass of stars has taken over two million years to reach us.
