Tony Crowther at this time had started doing electron microscopy from the work on viruses, he actually started doing micro... but I think you, John, taught him how to use the microscope.
[Q] Probably did, yes.
You must have, but I can't remember, did you take pictures of the amyloid?
[Q] No, I think it was Tony.
It was Tony Crowther. So Tony Crowther and [Claude] Wischik worked on these fibres and we... and we developed an antibody in Cesar Milstein's group to label these. This was done by a chap called [Michal] Novak working with... so that we could then prove definitely the material that came out of the brains was the paired helical filament. Because you could see it on the microscope labelled by antibodies and at the same time the preparations of course where you could tell the... how much material you extract from the brain by antibody labelling and primulin labelling also was used at the same time. So in the end we were the first people to extract the paired helical filaments, and they did look like filaments in the microscope. Kidd was right, in the sections they did look like a pair, they aren't actually paired helical filaments they're really a single helix, bit like actin, you can describe them in different ways. As a single helix if you look at the... you can think of it in terms of two cross filaments but of course it's a single helix. So at this stage I got quite interested because I did devise the plan of action and I thought, well, now the next thing is to identify the protein, we get it out and the thing to do is to clone... cloning protein had just been introduced. Now there's no cloning going on in structural studies.