Probably their weakest album, finding the group trying to blend progressive elements with lumpy hard rock boogie on obscure, extended tracks. The songs do look forward to the Electric Light Orchestra, for good or ill, in the helium-like high harmonies and the wide palette of instruments. Most of the multi-instrumentation is provided by Roy Wood, who picks up oboe, sitar, slide guitar, cello, and saxophone in addition to his usual guitar chores. Includes the British Top Ten single "Brontosaurus."