Human beings have always felt the need to measure time in some way, from the earliest sundials. Today we will learn how to making an hourglass.
The hourglasses have been used for centuries and centuries. The earliest example of one is in a 14th century painting, although the Romans already used them. Today they are usually kept more as a decorative object, as they have been replaced by the watches and the stopwatches that are built into virtually all current and future watches digital. However, most of today's board games still contain one to measure small portions of time (30 seconds or one minute). They are also often used visually in television programmes, so they are still present in the popular imagination. Let's learn how to make one.
You will need:
- An empty bottle.
- An empty, transparent glass bottle.
- Fine dry sand.
- Scissors, pencil and ruler.
- A stopwatch.
First we take the empty bottle and make a small hole in the tip of the stopper. Then we cut off the bottom half, i.e. the bottom.
Then we take the transparent glass bottle and make marks along its length every half centimetre.
Now fill the transparent bottle with the fine sand and place it on top of the glass bottle. We will need a clock or stopwatch to calculate the seconds it takes for the sand to reach the first line, the second, and so on. We can mark the time that each mark represents on the bottle so that we don't have to count it every time we use it.
We can also make more distant marks (every centimetre or every centimetre and a half) if we want to measure more spaced times.
The materials we have indicated are lighter for the upper part, and heavier glass for the lower part, for obvious reasons. However, if we work hard and make an old-fashioned wooden side support, we can join two glass bottles together, which looks more beautiful and archaic.
If we want to turn it upside down, we must cover the bottom, make marks again and use a rigid support, as the plastic would not support the weight of the glass.
We already have our craftsman hourglass!