the snake (symbol)
The snake is more than just a single animal that is threatening the drover's wife and her children; rather, it operates as a symbol of evil and the dark forces that menace the family. The snake's symbolism derives from the book of Genesis, and beyond that its many biblical associations with the devil. This is why the snake is such a disconcerting and effective animal for the drover's wife to have to vanquish as opposed to, say, one of the bullocks: it represents so much more than just a dangerous animal.
the empty woodpile (symbol)
The empty woodpile as stacked by the aboriginal man is a symbol for the empty hopes and dreams of the drover's wife; both her dreams and the woodpile come crashing down upon her. It also symbolizes the emptiness of the aboriginal man's life, and by extension, the ruination of aboriginal society: a former king, he is reduced to stacking wood for a poor white woman, and listening to her platitudes about not being lazy.
animals (motif)
Animals are often mentioned in the text—Alligator, the cattle, the bullock, the snake, the kangaroos—and they vary in terms of their value and the level of "civilization" they reflect. While the most domesticated and least wild animal, the cattle, is the most valuable (but easily threatened), this correlation does not always hold. Alligator straddles the line between civilized and wild, but he is of immense value for his ability to keep the family safe. Kangaroos are very wild but are not threatening whatsoever, whereas snakes and bullocks are also very wild but are immensely threatening. The reason this analysis matters to an overall understanding of the text is that, similarly, the drover's wife possesses many of the hallmarks of civilization, but is also very much part of the bush. She knows how to survive, she knows how to be tough and use her wits and fight back when she needs to. No human who wants to survive in the bush can forgo either her civilization (and hence fragility) or her natural instincts (and hence toughness); this duality is what makes life possible.
the aboriginal man (allegory)
The aboriginal man is not simply one man who is aggrieved by the presence of white settlers and rues his loss of power. Rather, he is an allegorical figure because he represents the larger destruction of the aboriginal people and culture. He was once a "King" and is the "last of his tribe;" similarly, all aborigines face the loss of their land, power, and culture. They are all forced to adapt to the Europeans in their presence and are subject to insult and stereotype, if not outright violence and political and economic marginalization. Lawson includes this man to suggest the deleterious effects of the European presence in Australia, and to encourage his readers to be more conscious of the way the aborigines were, and are, treated.