I have been thinking a lot this week about the long career of Nick Grimshaw, whose 75th. birthday was celebrated rather belatedly at the RA.  Besides thinking about what I think of as two of his best works, the Southern Cross Railway station in Melbourne with its parabolic roof and the Rensselaer Institute in Albany, New York, with its ovoid concert hall, what I remember best is a talk he gave at Wimbledon School of Art at the time of an exhibition of his architectural drawings in which he talked so fluently about the process of gestation of the structure of the Oxford Ice Rink whilst simultaneously illustrating the thought process by drawing on an epidiascope.