In the poem "Dust of Snow," the poet was in a depressed mood. When a crow shook the 'dust of snow' on him, his gloomy mood turned to one of optimism. The speaker realized that even though he was poor and had nothing, life went on. He felt better about himself and humanity in general. The speaker took the dust of snow into his mouth and blew it on the crows to show them that even though he was poor, he had enough spirit left over for friendship. This gesture showed the crows that even if the speaker was weak and powerless, he wasn't mean or cruel like some other people who lived in poverty. In fact, he showed them kindness by trying to cheer up their sad day with some laughter from a joke told by a friend. This act of kindness made the crows feel good about themselves and their world again. This is what the speaker's heart was given: the power to make others happy. This is how it changed him from a negative person who felt down about life to an optimistic one who could see the good in everything.