Images of slavery and freedom

Identify doulgass's tone in each of the following parts of his apostrophe to the ships of the Chesapeake bay.

"You are loosed from your moorings and are free; I am fast in my chains and am a slave! You move merrily before the gentle gale, and I sadly before the bloody whip, and I sadly before the bloody whip! You are freedom's swift-winged angels, that fly round the world; I am confined in bands of iron!