Kate Bush started her career at the top, the spellbinding 'Wuthering Heights' giving her a number one hit single with her first release. Yet from there, artistically at least, the only way has been up. For while the sales of both singles and albums over the five decades since have had their peaks and troughs, every new release has seen Bush refuse to be boxed in by past success but instead continue to take the musical chances that have characterised...