Metaphor for freedom
The convicts live a life marked by a lack of freedom and by a lack of possibility. They are almost slaves and are forced to obey the people put by the British government to control them. The characters all know that there is a high chance they will never return back to their homeland and will never be allowed to taste freedom again. In this context, the characters try to do everything they can to feel free which in their case means having sex with one another. The convicts are allowed to have sexual intercourse with one another and they take advantage of this little freedom. Thus, for them, sex is a metaphor used here to represent freedom.
Metaphor for confinement
Another important element for the inmates is the ship which takes then to Australia. For them, their imprisonment starts the moment they step on the ship. It is important to note that the ship is described in greater detail even when compared with the camp where the bulk of the action takes place. The reason why the ship is such an important element is that it is used as a metaphor in the play. Thus, for the inmates, the ship is a metaphor for confinement while for the people in charge is a metaphor for complete control.
Education
Most of the people who are in charge of the camp refuse to believe that the inmates have the capacity to become functional members of society and that they can be one day set free and trusted not to turn back to their old ways. One of the main characters points out that most of the inmates did not had any form of education and as such never learned properly how to live a modern society. Some make the argument that by educating the inmates they can be saved and rehabilitated. Thus, because of this, education is used as a metaphor for hope and redemption.
Hangings
The people who were in charge of the camp argued that harsher punishments, namely death by hanging, could be a deterrent for the other inmates and could have the objective of scaring the convicts from ever thinking about breaking the law again. Other characters claim that this does not work for the inmates because, for them, the hangings are a form of public entertainment. By comparing the hanging with a play, the author wants to transmit the idea that more than often, those who ended up in prison came from really violent backgrounds where death and pain was a common fixture. Thus, instead of trying to scare them with something they experienced all their lives, the prison authority should focus instead on trying to reform them and bring them on the right path.
Like animals
Another important comparison that appears in the play and which is mentioned numerous times is that between the inmates and animals. Many men who were in charge of the inmates refused to see them as real human beings, equal with them and capable of experiencing the same things as they did. In a sense, the lieutenants and the other men in control dehumanized the convicts, making it easier to abuse them without feeling any type of remorse.
