In this example the words in BOLD Print represent the metalanguage you need to be using for this task.

Mark Knight, regular political cartoonist for the Herald Sun illustrated his view of Kevin Rudd’s economic rescue package by focusing on one specific element – the handout of money for insulation of homes. In doing this he immediately gains reader interest and engages them in consideration of Piggy’s rhetorical question ‘can you really insulate a whole economy?’ The atmosphere in the roof top is dark and bleak, suggesting a tone of depression for the regular readers of the publication who are most likely to be beneficiaries of some aspect of the economic package since most would be low to middle income earners.

The readers eye is drawn to the white space containing a ladder, and a tube being used by the PM to pump dollars into the rooftop to insulate it against the elements. Knight is successfully drawing an analogy between this ordinary home ceiling being insulated against the elements of the environment and the wider economy gaining insulation from the package. This appeals to readers sense of home security. The ordinary Australian worker is also highlighted as we see Rudd, dressed in overalls with his sleeves rolled up getting his hands dirty doing the work himself. He is shown as being involved in the issue in this way so readers can sense the desperation in his attempt to save the economy. In this way Knight clearly suggests Rudd is trying hard, but his efforts may be futile.

The futility of the plan is further explored through the facial expression of Rudd himself. He is narrow eyed and unsure of his efforts. He is an unlikely hero in this regard. The space in the dark roof, not yet filled with the flow of insulation, is vast. Central to the effectiveness of this cartoon is the readers understanding of the word ‘insulate’. To insulate is to protect from the elements. Home insulation is usually made of a durable material to keep out heat and cold. Knight parody’s Rudd’s ‘insulation’ through a pun on the word with the use of the dollar notes. The insulation, in the form of green dollar notes, is where Knight brings humour to the cartoon. Realistically paper money will do little to insulate.

The green colour is reminiscent of the power of the US ‘greenback’ on the world economy, effectively reminding readers that it is a powerful adversary in the economic world. Piggy’s rhetorical question reflects this futility effectively. The irony present in the use of paper that is of no value for the purposes for protection, given the drop in the value of the dollar, is not likely to be lost on a discerning reader.
The effective analogy of the roof insulation and the economic stimulus package is very accessible to readers. Piggy’s rhetorical question “can you really insulate a whole economy?’ clearly reinforces the point being made in the analogy and will make readers stop and consider the futility of Rudd’s overall rescue package which is what Knight has intended for readers to do.