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How can I count my chickens before they’re hatched?

1501060009It’s an old saying that you shouldn’t count your chickens before they’re hatched – because you might not get what you expected. But Fred shows you how you quite literally can count unhatched chickens, and know exactly what you’re going to get.

1501060002It takes 21 days for a chicken egg, like this to hatch – if it’s fertilised. We, of course, eat only unfertilised eggs. But if we have to wait three weeks to find out which ones are fertilised and which aren’t, how can our eggs ever be fresh?

1501060003Of course, there is a way of finding out much sooner than 21 days, but you need to look inside the egg. You could do that with X-rays or other medical imaging equipment, but that would be extremely expensive.

1501060004All you really need is a light bulb. Farmers used to use candles, and this technique is still called ‘candling the egg’; using light to see inside it. You can see there’s nothing inside this egg – it’s fresh and ready to eat.

1501060005But look at this egg – it looks completely different. There’s clearly something in there.

1501060006If you look closely, you can just see the air sac at the bottom, and there’s definitely something above it.

1501060008What could it be? Well, wait a few days, and out pops one of these – a lovely little chick.

1501060009-1This little fella is only one day old, and already he’s in the How2 studio. So: how can you count your chickens before they’re hatched? It’s easy – you candle the eggs.