atLerte= ae poe weltFt. aSee Loe er oeee a nee et 20, Highlights of the second necting, held in Albuquerquey September 15- 7; are set forth below. 21k We providea the Settish # ith blueprints, material specifications, and velévant theoretical and experimerital information related to our XW-47 warhead; Mark 28, ih, is, and ke warheads} and the” BELElED ‘for our TX-41 and TX-46 weapons nol under development, 2e. The British provided similar information on their highyield fission bomb, now in stockpile; 2,200-pound thermonuclear bomb; small eceerep device; two boosted fission designs; - planned 1,500-pound thermonuclear weapon; and proposed 6-inch gun device, 23. Both parties discussed in detail neutron sources for initiators, high explosive specifications, yields and designs, and mechanical and electrical components. 24. We have several observations resulting from these meeting. The British have performed experiments in i and their program in this regard approxima’es Looebt our own experiments of 1954-55, They have tested radiation-imp1o- Sion, two-stage devices corresponding to our state of knowledge of about 1954-55. me ee tal They fully understand the advantage of the land their state of knowledge is about the same Lo pebsaz b ba or somewhat better than ours of 1956, they do not have the In regard to initiators, ears initiator, but have proceeded toward developrent of en external neutron source of initiation. These sources, eae FryETED In high explosive 7 development, they have devised -15- at Part Itt