§ Q2. Mrs. Castleasked the Prime Minister whether he will request President Kennedy to make available to Her Majesty's Government the evidence, in the possession of the United States Government, on the basis of which the American seismologist, Professor Lewis Don Leet, claims that he has discovered a fool-proof method of detecting underground nuclear tests in order that Her Majesty's Government's scientific advisers may study it.
§ The Prime MinisterThere are regular exchanges of information between Her Majesty's Government's scientific advisers and those of the United States Government. The United States and British Governments have spent a great deal of time and money over many years in an attempt to find a satisfactory method of detecting and verifying underground tests, so they are naturally disposed to study hopefully any claim by a reputable scientist that the problem has been solved.
The Government's scientific advisers will study any evidence made available by Professor Lewis Don Leet.
§ Mrs. CastleIs the Prime Minister aware that if Professor Don Leet's claims 219 are correct, the differences between the Soviet Union and the West on inspection can be resolved and a test ban treaty negotiated? Is he not aware that the Russians are about to resume another round of tests and that we all deplore this? Will he not, therefore, urge both the Russians and the Americans to postpone all further tests until Professor Don Leet's claims have been tested?
§ The Prime MinisterNo, Sir. We have not any detailed information, and this may be an interesting addition to the scientific knowledge on this subject, but, of course, the fundamental problem remains of how, when a challenge is made, it is to be resolved.
§ Mr. GrimondIs the Prime Minister advised that simply by underground testing any nation can make such an overwhelming advance as to alter the whole balance of power without testing in the air?
§ The Prime MinisterWe have tried this in various ways. First, we suggested a ban on atmospheric tests. The Russians rejected that and said that they could accept only a complete ban. We replied, "All right, let us study how to have a complete ban". Then they said," We will not deal with the problem of underground tests when they are thrown up". And so we are still working. I do not consider it a fair picture to suggest that the British and Americans are the people who have held this up. We have done everything we can to be as flexible as possible.
§ Mr. GaitskellReverting to the claim by Professor Lewis Don Leet, can the Prime Minister say whether this is now being examined by the United States Government's scientists and whether our own scientists have yet been consulted on the matter?
§ The Prime MinisterI am having it looked into by our own scientists.
§ Mrs. CastleIs the Prime Minister aware that Professor Don Leet claims to have 90 per cent. certainty of detection at 1,500 miles from the point of explosion, 95 per cent. certainty a little nearer and 100 per cent. a little nearer still? Does not this mean, therefore, that what the Prime Minister is insisting upon in the way of inspection is not 220 necessary and that the world could be relieved of the shadow of these terrible tests if every effort were made to take these claims seriously and to stop tests in the meantime?
§ The Prime MinisterNo, Sir, I do not accept that as a fair representation of what we have been trying to do. We are perfectly ready to look at this or any new discovery. The problem still remains that when something has happened and it is not certain whether it is from artificial or natural causes, there is still the need to make an on-site inspection. It may be that that problem will be overcame, but even that stands upon the ipse dixit of the country. What happens if we say to a country, "Our scientists say you have made a test" and that country replies, "No, we have not"? There must be some agreed method by which the job can be done.
§ Q4. Mr. Shinwellasked the Prime Minister whether he has studied the further evidence sent to him by the hon. Member for Easington in regard to the radioactive fall-out consequent on the forthcoming atomic tests; and if he will call for a further examination of the problem by his scientific advisers in the light of this evidence.
§ The Prime MinisterThe right hon. Gentleman sent me a letter signed by a number of biologists which appeared in the Press last week. This letter contained no evidence about the effects of fall-out which has not already been published by the Government. These matters remain under continuing examination by the Government's scientific advisers.
§ Mr. ShinwellAs Professor Wadding-ton and his friends are eminent biologists, does not this indicate a conflict of opinion about radioactive fall-out? In the circumstances and in view of that conflict of opinion, would it not be advisable for the right hon. Gentleman to submit Professor Wadding-ton's letters, and any additional evidence that he may care to put forward, to his scientific advisers and then inform the House about their conclusions?
§ The Prime MinisterNo doubt our scientific advisers are fully conversant with these views. It all comes down to one point. Of course we deplore these tests, and of course we want to bring 221 them to an end. The only question is the balance of duty, and it is a hard duty to decide whether in the interests of defence and the situation in which we found ourselves a few weeks ago we must agree with our American friends to continue the tests or whether we should not do so. We have debated this matter, and we have discussed it. [HON. MEMBERS: "Not here."] We have discussed it in Question and Answer. I have made my statements, and I understand that it can be debated in two days' time.
§ Mr. ShinwellWill the right hon. Gentleman appreciate that I raised not the question of tests but the question of the consequences of tests, and that all I am asking—I think it is a perfectly reasonable submission—is that his scientific advisers should take note of any evidence that Professor Waddington, an eminent biologist, can adduce?
§ The Prime MinisterYes, Sir; of course we will do that. I will see that the evidence is studied by those whose duty it is to advise me.