Letter from Thomas Gold to Dr A C Damask, Department of Physics, Brookhaven National Laboratory, Upton, LI, New York Says that he is aware of welding and has also been told by Dr Smoluchowksi of 'the enhancement of this effect caused by radiation'. Says that he is glad that Dr Damask's experimental results confirm this. Also says that the Surveyor results show 'that the material is not very strongly sintered, in fact somewhat less so than I would have thought'. 17 June 1966