Well the canto ends with the poet talking about the value of fame and glory reached through great deeds.
Hot air goes up and the cold air goes down what the air currents forms when the atmosphere moves the excess hot air and warms the lower latitudes to the cooler air has high latitudes and so the air rushes in to replaces it. hopefully that help have a nice day :)
Federalism refers to the supremacy of he powers of state governments