Capable, astute
Douglass describes Mrs Auld as apt, and follows up on this definition by showing how she took her husbands advice and mixed with her own experience made a strong and smart conclusion about slavery and education. This shows that she is smart and capable of doing much.
A metaphor is a speech device that compares one object to another object using words that associate them. In this case, the lines that use this literary device is A which compares hemisphere as the master of its own house.
It's an example of allusion, because it alludes to the language in the Emancipation Proclamation.
Ask for clarification ofc....
