initially deane and woodward had planned for the interior walls to be of rubble which would then be plastered over. however, in early 1855 they submitted a design change to the board, deciding instead to use caen stone, and the board agreed. however, when they had learnt that only two thirds of the stone had arrived the board rescinded this permission. after strong argument from deane, on 4 may they board overruled their prior decision and agreed to the use of caen stone.