Letter from Thomas Gold to Ernest J Ott, Technical Assistant, Astronomy, National Aeronautics and Space Administration [NASA], Washington, DC Thanks Mr Ott for sending him the [RCA] Letter Progress Report, 3 June 1966 and goes onto discuss the report e.g. says that 'The need for a current regulator and the need for magnetic shielding and shading investigations has of course been discussed before and the steps described here clearly necessary. From the discussion given, I cannot decide which of the two methods of regulation will be preferable'. Also talks about TIGRIS e.g. says that 'I have been wondering in recent times whether we should not redirect our thoughts concerning the TIGRIS program towards manned space flight rather than sounding rockets'. 18 July 1966