The Turn of the Screw (opera) composer conducting. Described as one of the most dramatically appealing English operas, the opera in two acts has a prologue and sixteen scenes, each preceded by a variation on the twelve-note 'Screw' theme. Typically of Britten, the music mixes tonality and dissonance, with Britten's recurrent use of a twelve-tone figure being perhaps a nod to the approach of Arnold Schoenberg. Thematically, the play gives a central role to a line borrowed from W. B. Yeats' poem "The Second Coming": "The ceremony of innocence is drowned." The opera was given its British premiere on 6 October 1954 by the Sadler's Wells
Screw turbine Screw turbine The screw turbine is a water turbine which uses the principle of the Archimedean screw to convert the potential energy of water on an upstream level into work. It may be compared to the water wheel. The turbine consists of a rotor in the shape of an Archimedean screw which rotates in a semicircular trough. Water flows into the turbine and its weight presses down onto the blades of the turbine, which in turn forces the turbine to turn. Water flows freely off the end of the turbine into the river. The upper end of the screw is