These rhythms have hundreds of years of tradition behind every beat. Every group on this album consists of about ten talented percussionists. They employ 'toeres', a native form of wood-block, hand-carved from the 'Tamanu' tree, each of a different size and pitch. Several played together create a musical triad. A contrasting sound is sometimes furnished by the 'ofe', a section of split bamboo. The split section is raised and made rigid by inserting small pieces of bamboo at each end, and the instrument is played by hitting the raised slits with two bamboo sticks. The remainder of a Polynesian percussion orchestra consists of 'pahus', drums varying in size from tiny bongo-like instruments to the massive, deep-voiced bass drum, usually a hollowed-out coconut trunk covered by a sharkskin head. Each drummer has a rhythm of his own to perform, each more intricate as the drums gets smaller, and they all blend surprisingly into a definite syncopated pattern.