Write the contribution of Bu Ali Sina .

He was physician, philosopher, encyclopaedist, mathematician and astronomer of his time. His major contribution to medical science was his famous book al-Qanun, known as the "Canon" in the West. The Qanun fi al-Tibb is an immense encyclo- paedia of medicine extending over a million words.

because of its location and commercial importance, atlanta was used as a center for military operations and as a supply route by the confederate army during the civil war. therefore, it also became a target for the union army. general william tecumseh sherman and his troops captured the city in 1864.