If our eyes only saw frames (IE: 30 images a second), like a single lens reflex camera, we'd see images pop in and out of existance and that would really be annoying and not as advantagous to us in our three dimensional space and bodies.
In the Vienna of the second half of the 18th century, in addition to Haydn and Mozart, three symphonic composers, namely Leopold Hoffmann, Carl Ditters von Dittersdorf and J.B. Vanhal helped further the development of the symphony.
The djembe drum is said to have been invented in the 12th Century by the Mandinke tribe in what is now Mali, in West Africa. It has been played by West Africans for generations forming an integral part of ritualistic life in Mali, Guinea, Senegal and other neighbouring West African countries.