I like this simile for an implacable nature, though in this case, let us mention that Poyser is only implacable in the face of bad farming.  In many other respects he is kind and good-natured.  Later, when he is facing the consequences of others’ behaviour, he is in turn shown a certain mercy.

‘Martin Poyser was as hard and implacable as the north-east wind.’

See another simile for hardness in human nature.

Source: George Eliot, Adam Bede (Harmondsworth: Penguin, 1985 (1859)), p. 188

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