Consider Douglass's speech "What to the Slave is the Fourth of July?" What logic does he use to make his point?

Consider Douglass's speech "What to the Slave is the Fourth of July?" What logic does he use to make his point? His speech contains a lot of emotion, including anger. His anger is certainly justified, but does his anger take away from the effectiveness from his argument? Describe a time when you argued a position you were angry about. Were you able to make an effective argument? Why or why not?