Correspondence regarding the Isaac Newton Telescope correcting plate, including correspondence with the manufacturers Chance Bros. and Pilkington Bros. Ltd concerning stirring white plate glass, and with Schott on the supply of a large UBK 7 disk; correspondence with R. Atkinson, H. Spencer Jones and G.M. Sisson, with G.E. Manville's report of a visit to Pilkington Bros. to examine the stirred white plate; letters concerning a meeting with Dr Hampton of Chance Bros. and L.H.A. Pilkington on 11 February 1955 at the London Office of Sir Howard Grubb, Parsons and Co. Ltd; measurements of the ultraviolet transmission curve for Schott UBK 7 and Chance glasses; correspondence with Hilger and Watts Ltd on ultraviolet glass; and a copy of a letter from H. Spencer Jones to Vice-Admiral Archibald Day, Hydrographer of the Navy, 4 April 1955, informing him of the Isaac Newton Telescope Board of Management's decisions regarding the purchase of correcting plate glass and the sheets of stirred white plate glass. |