Blackett then suggested that I studied the very large cosmic ray air showers, which had been discovered by Pierre Auger in Paris. They were then, and I think still are known as the Auger showers, and the question was: what is the energy of the particles from space, impacting on the upper atmosphere to give such energetic processes in the atmosphere?

I then worked first of all with Jånossy, a refugee from Hungary who had built an enormous block of lead to study these particles, and secondly with JG Wilson, whom Blackett had brought with him from London, and Wilson and I had set up two cloud chambers, separated by increasing distances in the Schuster Laboratory and measuring within an arrangement of Geiger counters, so that they were only triggered when there were particles in both of these chambers. And we very quickly measured particles of very high energies, or rather the result of the impact on our equipment, very high energies.

And I think my memory may be not quite right but I believe that we wrote letters to Nature. I wrote one with Wilson and one with Jånossy, in which we said we were dealing with particles which had impacted on the atmosphere with energies of the order of 10¹6 electrons volts. Well, one might think that all this was a very happy time, but it was not. There was a terrible background, which began in Bristol with Hitler re-arming, marching across... beginning his march across Europe into the Rhinelands, with Mussolini invading Abyssinia and then in 1936 with the civil war beginning in Spain, so the time was full of great anxiety. And I remember in Bristol there were already many refugees working, and I had quite a large room in which I was studying my conductivity rubidium films and one day a German joined me. He was working on something different, but in another part of the room and I certainly did not like him, and in the next room a person called Fuchs arrived.

Well, now... Fuchs I disliked from the very beginning. He was extremely inquisitive and I never got on with him. Fortunately, he... we were not in the same room and I might remind you, though it’s not part of my story, that he was, after the war, arrested as a spy because... he was working at Harwell... because of releasing the secrets of the atomic bomb to the Russians. That is by the way. Most of my association with the refugees was extremely happy and profitable ones.