Tonight while cleaning your teeth, you might like to reflect on the amazing invention of the mirror. We take them for granted, but the modern mirror is a remarkable invention.
The mirrors we use are also relatively recent. The oldest known mirrors were polished obsidian, dating back to Turkey around 6000 BC.
After that time, there are various examples using alloys such as bronze. These would have been expensive, uncommon and not particularly good. They would not match the quality and price of the mirrors we use today.
With current manufacturing techniques, aluminium is vaporised in a vacuum, and bonded to the glass surface. This makes a good reflector that doesn't modify the colour.
That's a start, but still not up to scratch if the glass is not perfectly smooth. Any imperfections will distort the image, and spoil your face with bumps and hollows that aren't there.
Metal-backed glass mirrors did appear around the first century AD, but the poor quality glass did not work well.
Producing good plate glass has only been possible since 1687 when Bernard Perrot of Orleans made quality plate glass by pouring liquid glass onto an iron table, then rolling it.
The cheap modern method of producing glass was devised in 1959 by Alistair Pilkington. Molten glass is poured on top of molten tin. It's perfectly flat and doesn't need further rolling or polishing.
Mirrors have interesting psychological effects. Nature did not prepare us to deal with the sight of that strange person peering back at us. In one building where the lift service was slow, they installed mirrors to distract impatient travellers.
Humans are one of the few species who realise that the image is a reflected self. We can't ask them, but we think that other animals such as orang-utans recognise themselves because they will try to remove a spot placed on their forehead.
You will have seen peewees attacking the invading bird in the mirror.
Pigs don't see themselves, but experiments have shown they can use a mirror to locate food hidden behind a wall.
Perhaps for them it's a relief to be spared worrying - do I look big in this?
The Fuzzy Logic Science Show is at 11am Sundays on 2xx 98.3FM.
Send your questions to AskFuzzy@Zoho.com; Podcast: FuzzyLogicOn2xx.Podbean.com
