I must now begin the story of the steerable radio telescope. With that even, with Hughes' map of the galaxy, it suddenly became clear to me that it would be marvellous if we could have a telescope of the size of the 218 foot Transit Telescope, which we could direct to any part of the sky. It seemed that we would stand much more chance, we knew very little about the great cosmic ray air showers, what effect the specular reflection would have, and whether it would be more profitable for us to look at lower elevation than in the zenith. And one day, with some trepidation, I mentioned this to Blackett, and I thought he would think it was a crazy idea that we would be able to build a telescope of that size, and move about and direct to any part of the sky. On the contrary, he was... became immediately excited. He was always, as I might have said earlier, fascinated by anything to do with the exploration of the universe, and having been possessed, as we all were, by the quite unknown... quite unknown where these enormous energies of the cosmic rays, not the cosmic radio emission, the cosmic rays, emanated in the universe. And he simply said to me, 'Well, look, if you can find somebody who could, might be interested and capable of building such a telescope, we'll think about it'.
And I think it was in 1949 that I first made some enquiries. Now, it didn't seem to me then to be all that difficult. I remember I had been putting six foot aerials under the fuses of the bombers, and flying them at 30,000 feet, and I thought, well, if it was possible to do that, surely it would be much easier to build a very large telescope fixed on the ground? I'm afraid I was mistaken. My initial enquiries to some of the firms that I'd been engaged with during the war received a very negative response. The responses were of two kinds; either that they were too busy on work of national importance, or that it was impossible to build the sort of instrument that I had in mind.
Then I had the idea of approaching Sisson, who was then the Head of the Grubb Parsons Newcastle works, dealing with the manufacture of telescope mirrors, and in fact, he had constructed most of the telescope mirrors of... which were then working in various parts of the world. Now, Sisson, he came to see me at Jodrell Bank because I had got to know him pretty well, and for other reasons, and I told him what I had in mind, but I said, 'You know, so far people say it's impossible. And he said, 'No, I don't think it's impossible'. And I said, 'Well, are you and your firm, Grubb Parsons, will be interested in looking into this?' And he said, 'No, we couldn't do... we're not equipped to build that sort of instrument'. He said, 'But we will be very interested in making the control system for you'. He said, 'But on the other hand, I do know a firm who might well be interested in your project'.