We... I had... my equipment... officer had our own equipment then which were being built in the aircraft, but I had quite a large ground equipment. On which I was constantly putting improvements and on this field at Leeson House, looking across the bay at Swanage, I could easily see ships and so on, and one day we arranged for a submarine, HMS Usk, to come into the bay and lo and behold, there was a clear echo from the submarine on our screen. And we summoned the people from the Admiralty Signal School and, you know, this was an amazing diversion of our efforts.

After some doubts, we demonstrated that we could detect this submarine at a range of eight or ten miles, and we... I drove the equipment down to... I think it was Peveril Point over Swanage Bay, and there demonstrated this and they said, 'Oh well, of course, if we ever put this on a destroyer, the roll and the rock' and I said, 'That's no problem, instead of using a paraboloid, we'll use a cylindrical paraboloid, which has... although it has a narrow beam and azimuth has a very, very broad beam and elevation, so if your ship rolls, you won't lose the echo'. And it was just before Christmas of 1940 that they took my equipment away to the Signal School in Portsmouth and I thought: oh dear, it's going to be a long time before I see any result of that. I was completely mistaken. In a remarkably short time, within months, they had this equipment working at sea, on a Corvette and that's the story of how centimetres got into the Admiralty.

The other diversion we had was in using the centimetre technique to direct the anti-aircraft guns. This we put another person... another person was put in charge of that. I had nothing to do with it but it was not terribly successful it was eventually... a brilliant system was eventually made and used later in the war by the Americans and we will come to the American story in due course.