Final answer:
The words "rusty" and "old" contribute to the depth of a metaphor by adding images of degradation, weariness, and time's effects, which enhance the overall mood and message.
Step-by-step explanation:
The words "rusty" and "old" deeply enhance the meaning of a metaphor by providing imagery and connotations that evoke feelings of decay, neglect, and the passage of time. These terms suggest a certain weariness and deterioration, much like the subjects they are describing within the metaphor. For instance, an "old" sailboat canted on her bilge evokes a scene of desolation and abandonment. "Rusty", pertaining to the slow chemical reaction of iron oxidizing, lends itself to the metaphor by implying a slow, inevitable decline and degradation, such as that seen in the iron chains described as giving off heat as they rust. Additionally, the use of "ash" to describe trees in a metaphorical sense not only fits the rhythm, but adds layers of desolation and death, echoing the phrase "ashes to ashes," indicating completion and finality to a once vibrant existence.