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The Cell - The Hidden Kingdom (Part 2/6)

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I'll be able to see what van Leeuwenhoek saw. Now I've looked down a fair few microscopes in my time and this is nothing like anything I've used before. It's fiendishly difficult to use, so I've got Hans with me just in case I can't see a thing. So what do I actually do? Where am I looking? Er the wrong side - you must look through this hole. A very tiny hole. And there's a lens in it. Yes. And the lens - through the lens you see the sample - that is put between the glass. OK, so if I hold it up to the light, like this, Close to your eyes And I can see - I can see green. There is a focusing knob. There's a focus! Yes, there is a focusing knob. This might be made - So I can move it actually away from my eye. This one - this is the focusing knob. Let me try now. It's so simple and it works so well. Yeah - that works. That really works. It's now in focus. Oh wow! Oh my God, you can actually see moving creatures. Oh God that's incredible. There's a tiny tiny bug in there. Which is scooting around, which I guess is a protozoa. That's astonishing. I know this story. But I didn't think this was what I was going to actually see. It's just like looking down a modern microscope in fact, even though it's completely different to use.

Van Leeuwenhoek gushed with delight too writing, 'This was to me, among all the marvels that I have discovered in nature, the most marvellous of all. No greater pleasure has yet come to my eye than these spectacles of so many thousands of living creatures in a small drop of water, moving among one another.' And so in the seventeenth century, when people were discovering Australia, and astronomers were exploring the heavens, so van Leeuwenhoek was peering into a new, microscopic universe. The full meaning of what he saw in that universe , seen here down a modern microscope, escaped van Leeuwenhoek. He assumed he was seeing miniaturised versions of everyday animals, with beating hearts and contracting muscles, just like their larger counterparts. He called them 'animalcules'. Little did he know it wasn't just a question of scale. Van Leeuwenhoek's discovery was the beginning of a scientific revolution. He had seen new forms of life. We now know he was looking at microscopic plants and single-celled animals such as amoeba. This Dutch draper was the very first person to see individual living cells.

This revelation could easily have been lost to science because van Leeuwenhoek was an obscure linen merchant, working on his own. He himself was afraid of being ignored, and winged, 'I suffer many contradictions, and oft times hear it said that I do but tell fairy tales about the little animals.' He sent his notes off to the wise gentlemen of London, more in desperation than hope. King Charles the Second had granted the Royal Society its charter in 1662, with the motto, 'Take nobody's word for it'. The Fellows were pretty sceptical of van Leeuwenhoek's claims. Even so, they turned to one of their most famous members, our very own Robert Hook. He was the go-to guy when you had very small things to investigate. A decade earlier, he'd spent several years looking down his own microscope to see what he could find. Hook had written one of the most important books in early biology. Important not just for what he saw, but for how he described it.

So this is it, this is 'Micrographia'. This is the 'Micrographia', yes, this is the first edition as it would have been seen by Fellows of the Royal Society in the 1660s. The title page is here: 'Micrographia, or some physiological descriptions of minute bodies made by magnifying glasses'. So he calls them magnifying glasses rather than microscopes at this stage. That's right, and really this was the first book of microscopy, so you can see why there was a slight uncertainty about terms - he was doing it for the first time, effectively. So at the time, this is near the beginning of the Royal Society's - my goodness, let's have a look at this dedication: 'To the King'. God - that's a big font, isn't it? That's real deference there. Yeah it is, and very great deference: 'We do here most humbly lay the small present at Your Majesty's royal feet.' Now that Hook was a famously cantankerous man and he annoyed a lot of his contemporaries, did he not? Is this sincere? It sounds a little bit sarcastic to me. I think it is - it's formulaic. I want to see some of the specimens. There's the head of a fly, so you get the compound eyes there. That's incredible. This is a seventeenth century drawing. I mean it looks exactly like a modern electron micrograph. Yeah and this is the first real view that a general audience had of this kind of world of the very small.

The drawings alone make this book special. But it's the language Hook uses when he turns his microscope on cork that makes it a landmark in science. And looking at cork he then coined the word 'cell'. So here's the sentence right here: 'Partitions of those pores were nearest thin in proportion to their pores as those thin films of wax in a honeycomb which enclose and constitute the hexangular - is that hexangular? sexangular cells. Next, that these pores, or cells, were not very deep, but consisted of a great many little boxes.' So this is it, this is the moment when he writes the word 'cells' to describe what he's looking at - the individual units that make up a cork structure. That's right, and self-contained units is what he's saying from the description. It's incredible, I mean this is a real piece of history, this is the moment where the biggest field in biology was born. It's a genuine first.

We now know that Hook was indeed looking at the basic building blocks of plants: cells. But back in 1664, Hook thought he was seeing something very different: narrow channels or pipes that carried sap up and down the plant. And nowhere in Micrographia does he mention the living animalcules van Leeuwenhoek had described. Hook had never seen them. So imagine his irritation when the letters from Delft arrived over a decade later. With a bruised ego, he dusted off his own microscope, a very different design from that of van Leeuwenhoek's: larger, but less powerful. Trying to copy his work, Hook took samples from the River Thames, brought them back, looked at them under the microscope, and he saw - nothing. Absolutely nothing. Here are his notes, and his comment speaks volumes about the time in which he was working. I concluded therefore that either my microscope was not so good as the one he made use of, or that Holland might be more proper for the production of such little creatures than England.

Hook might have jacked it in at this point: 'Bah: they're only found in Holland!' But that wasn't his style. Hour after hour, day after day, he stuck with it. He tried to cram more light into his microscope. He ramped up the magnification. And then, within a fortnight, Hook finally saw them for the first time. Van Leeuwenhoek had been right all along. The tiny animals were the real deal. Now, the stuffy fellows of the Royal Society did get excited. Though, like van Leeuwenhoek, none of them really knew what they were. What they did realise, for the very first time, was that there was quite literally more to life than meets the eye: a whole kingdom of miniscule creatures whose existence they'd never imagined. It was a shocking revelation: the natural world was quite simply not as it had seemed. In 1680, the Royal Society made van Leeuwenhoek a Fellow, and formally declared him the discoverer of the little animals. This is his certificate, and here he is, looking justifiably smug. He was the most famous man

Video Details

Duration: 10 minutes
Country: United Kingdom
Language: English
Producer: BBC Four
Views: 2,789
Posted by: vallisso on Oct 28, 2009

Episode 1 of 3

Dr Adam Rutherford introduces a new three-part series that tells the extraordinary story of the scientific quest to discover the secrets of the cell and of life itself. Every living thing is made of cells, microscopic building blocks of almost unimaginable power and complexity.

What is life and where does it come from? are two of the key questions asked by Rutherford. Well chief among the stars of this opening episode is 17th-century Dutch linen merchant Antonie van Leeuwenhoek, now known as the father of microbiology, whose work on an amazing viewing machine (an early microscope) transformed the way we see the world, and kicked off the journey to answering that question about where life came from.

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