Transcription of the lecture in Cavendish LabNo.

7th August, 2014

Name

“The History of Cavendish Laboratory”
By Dr. Steve Martin
Where did Cavendish Laboratory start? The answer is here, in the middle of town. Youmay have seen that in the middle of Cambridge. So, more of that in a minute. That is theview you most certainly have seen in Cambridge. That’s the old (1)thatwas founded by William Cavendish. You saw his picture downstairs.
When I was a (2)student, that’s where I went for my lectures and mylaboratory practicals. It’s been a world leader for 200 years, has a tremendous history, ofwhich I will tell you a little, but more important than an impressive history, is we thinkthat it has an impressive (3), because it’s growing so much and doing so many
new things. I will have a very, very brief look at one or two of those as well. But before
we do that, let’s have a look at one or two famous people who’ve worked here and made ahuge (4)to Physics. See if you can recognize them.
Now, James Clerk Maxwell. Any ideas what he did? Any thoughts? The father ofelectromagnetism. He devised four fairly simple (5)which described all of
the behavior of (6)and (7). And that was in the middle ofthe 19th century.
One of you, have already told me about J.J. Thomson. In a minute, we’ll actually see this.
That you may have seen that in textbooks as being the equipment that he used forchecking the charge compared with the (8), the charge-mass ratio of the(9). I think one in our cupboard is actually a copy, because the original is too
valuable to even have out on display. But you already know about J.J. Thomson.
Let’s move this forward to about 1900, somewhere near there. Now, do you have anyidea what this is? You’ll see this one as well, in a minute. Any idea what that piece
apparatus is? The Cloud Chamber, the (10)which allows us to see subatomic(11). It creates in a cloud, a trace made of condensed (12), fineliquid droplets. There is a much more modern version of this. I will show you in themuseum, in which you’ll see (13)rays which links very nicely with your talkdoesn’t it? I checked it, some days it depends on the weather. Some days, the machinedoesn’t show any cosmic rays at all. This morning we’ll have plenty of them, I think we’ll
see some good cosmic rays today, however. So, cosmic rays in a few minutes time.

1Now, any idea what we associate with Ernest Rutherford? The idea that the (14)has a small (15)inside a very big space. That was his idea, but most of thework was done by his research students, Geiger and Marsden. So, although it’s called
the Rutherford nuclear atom, it’s Geiger and Marsden’s experiment that demonstrates
it.
Now, this takes us to around 1960’s…ish. What did they discover? (16)
. Exactly.
In fact, if you go to that gateway I showed you earlier on, I believe the room where theyrealized about DNA is the one about three windows to the left. And it is a public house, adrinking place, at the end of the street where many people have been reputed to rushout of the Cavendish, having made some sort of discovery, like we’ve split the atom, wediscovered the secret of life. Are we clever?
Yes, of course we look out into space, discovering things like (17)and what
have you. That’s actually out of town. That’s about 5 miles, about 8 kilometers, over theway on the other side of town and its part of our observatory and that is still in theforefront of radio (18). And yes of course, some of our scientists complete towork of CERN. In the same way, I’m sure many Japanese scientists were out there.
Almost every year, I end up going up to CERN for something. It’s always nice to go toGeneva, and you meet people from every country in the world there in one commoncourse. Still busy even though they found the (19), they still havework to do. They’re simply busy at it. So we do contribute to that and to work at
Fermilab as well. Now this is rather fun.
Now, this is even cleverer. One single (20)
. I’m told that the cell which issuffering with cancer has different (21)properties compared with one that isnormal. So instead of testing a large piece of (22), just testing one cell,
scratching it, healthy cells, cells with cancer as a disease behave differently; andtherefore I can tell the difference with the sample of one, just one, cell. Amazing what
you can do with (23)
if you try.
Now that was a very small sample. Just by way of introduction. If you are interested inthis, and you want to be able to read about it at a sensible speed, if you just click on theCavendish website, just type in Cavendish Laboratory. This is actually one of ourwebpages and you can see I’ve stolen, at least some of the illustrations from there. If you
want to find out what’s inside each one of those, do please go and search on the web andyou’ll find all sorts of interesting things.

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