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| Have you ever been for a walk in the wind? How strong was it?
Was it strong enough to blow you off your feet? Was it strong enough for you to lean into without falling over?
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| The Big Question is - how do we describe the wind?
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| You might not think it matters that much - but it's very important for people like aircraft pilots and sailors.
They need to know how windy it's going to be for safety.
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One of the best ways to describe the wind is to give it a number from something called the Beaufort Scale.
This was invented by a British Naval Officer - Francis Beaufort - almost 200 years ago.
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| Back then, sailors all had their own way of describing how windy it was. This made things very confusing!
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| Beaufort decided to use numbers.
Zero is complete calm - a boat would just stay where it was in the water.
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Three is a gentle breeze...
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...nine is a strong gale...
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...and twelve - the maximum - is a hurricane!
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The British Navy used the Beaufort Scale, but apart from them, no-one else really bothered - until a terrible sailing disaster.
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In 1854, both French and British supply ships were wrecked during a terrible storm.
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So to prevent this happening again, the British Navy and French Navy decided to employ people to watch the weather for them.
So all over the world, people began to measure and record the wind, and send the measurements to each other by telegraph.
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This gadget is called a cup animometer, and it had just been invented around this time.
By counting the number of turns it makes in a minute, you can work out exactly how fast the wind is travelling. The faster the animometer, the faster the wind!
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So the Royal Navy insisted that the meteorologists turned their animometer readings into the Beaufort numbers.
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But to make things worse, meteorologists didn't really understand the Beaufort Scale.
What exactly does this mean, for example?
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When they tried to convert their readings, they just got it all wrong.
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So, 70 years ago, the world meteorology association decided to update the Beaufort scale.
Nowadays, the Beaufort numbers refer to the number of turns of an animometer.
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And this is what meteorologists and sailors use today to describe the wind.
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