Tomorrow night David Norris performs his one-man show, a Joycean evening, in aid of Friends of TCD Library, at the Edmund Burke Theatre - wine reception at 7.30 p.m. (phone 01-6082320 for information) . . . Parley of Instruments will hold a work- shop in early music at the School of Music, TCD, on Sunday - contact 01-2803870/01- 4538696 . . . Purgatory, a new opera by Michael Scott based on the play of the same name by Yeats, opens at the RHA Gallagher Gallery on Thursday.