When I was working as an independent at the village of Bowerchalke in Wiltshire in the, it'll be in the 1960s, late 1960s and early 70s, I used to notice that during the summertime the atmosphere became very hazy, visibility ranges dropped to only a few hundred yards sometimes when the wind was from the East. From Europe.

And I'd been in Los Angeles, and I knew what smog was and it looked and smelt to me exactly like smog. I asked my friends who work for the meteorological office if it was possible there was smog in England because we didn't believe in smog here in those days. There was only winter smogs in a place like London when coal burning and that had all stopped. And they said, 'Oh no, it can't be smog it must be some agricultural haze or something like that'. But it smelt like smog and I got kind of puzzled so, I thought, well the only way to prove it was be to demonstrate that there is something in the air when the hazy air appears over Bowerchalke, that is unequivocally of human industrial origin. It's not a natural compound. Something that comes from cities or conurbations of people. And the best thing that I could think of were the chlorofluorocarbons because they are purely man-made, there is no natural source of them whatever and they mainly come from cities, great conurbations of people. So, the next time there was a haze, I measured the chlorofluorocarbons in the air and to my delight, they were three times as abundant in smoggy air as they were in the clear air that preceded the smog. So that kind of proved the point. And I also did the same measurements in far Western Ireland, which showed that the smog would travel even as far, right across as Bantry Bay and those regions. And it turned out that it came mainly from the cars of the millions of holiday makers in Southern France and Italy during the summertime. That's where the smog was produced and the air blew it all the way across the Southern England to Ireland. But I also found in Ireland that when the air came in from the Atlantic, it had quite a lot of chlorofluorocarbons in it. And I thought, well are these coming from America all the way across the Atlantic, or are the building up in the world, because they're such inert compounds there's nothing to remove them. And, at that time my friend Peter Felgate [?], who was professor of cybernetics at Reading University said to me, 'Well why don't you apply for a grant to the Natural Environment Research Council, Science Research Council to ask if they would let you go on one of their ships like the Shackleton down to Antarctica and back and take measurements of the CFCs [chlorofluorocarbons] in the atmosphere right the way across the world. This will prove whether they are building up in the atmosphere or not'.

So, I sent in my grant proposal to NERC and SERC and waited and they came back, promptly, cast out by the peer review committee. In fact, they were very cross about, one senior chemist on the review, among the reviewers said that 'this is a bogus proposal and they time of our committee shouldn't be wasted with proposals like that. Every school boy knows that the chlorofluorocarbons are amongst the most inert compounds known to man, it will be exceedingly difficult to measure them at the parts per million level and yet this clown is claiming he can measure them at the parts per trillion level. This is a bad proposal, don't waste our time with this sort of thing any more.'

Now, the civil servants at NERC, interestingly, were rather upset by this. Now, they couldn't do anything about it, they couldn't give me a grant because it has to be approved by… but what they could do was to let me travel on the ship with my home-made apparatus and do the measurements. And one of their representatives, a lady called Mrs Howells came to see me, to see that the apparatus really did work and could measure these things in the atmosphere and then told me that I could go on the Shackleton and they would pay my fare back from Montevideo, which was all I needed.

So, with a few hundred pounds I made the equipment and went down there and of course those were the measurements that started the ozone war, the ozone problems, depletion problems. But also, the same measurements, I measured the gas dimethyl sulphide in the atmosphere right the way across the world, and showed that it is the natural carrier of sulphur in nature and this has turned out to be a far more important discovery in many ways because we now know there would be no clouds over the oceans were it not for this gas coming from the sea. And this has climatic consequences of great importance. Without clouds the world would be 20 degrees Celsius warmer than it is now.