Mercury is a messenger God sent by Jupiter to seek a compromise with Prometheus during his imprisonment on the mountain, as Panthea and Ione watch from a nearby peak. Mercury is portrayed as a well-meaning but weak character. It is painful for him to see Prometheus suffer and he shows disdain for the Furies, who are waiting eagerly for Prometheus to reject Jupiter’s compromise so that they can torture him. Mercury pleads with Prometheus to accept Jupiter’s offer and this demonstrates that Mercury, unlike Prometheus, sees the value in negotiation and reaching an agreement which, to an extent, pleases both parties. Prometheus, however, views this course of action as self-serving, implicitly suggesting Mercury’s willingness to value personal gain over the greater good. Mercury’s weakness thus serves to highlight Prometheus’s strength, in that he is willing to sacrifice his own wellbeing for the sake of humanity even though an escape from his torment has been offered. Mercury is clearly a powerful God, as he is the messenger for Jupiter and is able to frighten and hold off the Furies. His decision to work for rather than resist Jupiter, therefore, can be viewed as a personal weakness rather than a lack of knowledge or power. Shelley’s depiction of Mercury draws upon Roman mythology, in which Mercury is a messenger god who negotiates between the realm of gods and the human world. He also frequently represents commerce, trade, and negotiation in classical stories.