Why did edward kamau brathwaite write the limbo poem?

The Limbo Dance is believed that it was invented on the slavery ships by the slaves themselves as a way of keeping fit in confined conditions. The poem is telling a story of the limbo dance, however, at the same time telling a story of slavery. For example: "stick hit sound" This suggests the sound of someone hitting a stick to the beat of the music, but at the same time, the sound of a slave being hit by a stick. Another one is "down down down" This suggests the stick being lowered in the dance but, at the same time, it telling us about the slaves being taken down to the bottom of the ship and it could also be their feelings; "down down down" - their hope and happiness being brought down to despair and misery.