What did boxer throw on the fire animal farm?

In George Orwell's "Animal Farm," Boxer, the hardworking cart-horse, throws his straw hat onto the fire as a gesture of solidarity when the animals are burning the windmill in a moment of despair. This act symbolizes his dedication and sacrifice for the cause of the animals' rebellion against human oppression. It reflects Boxer's unwavering commitment to the farm's ideals, even as the situation becomes increasingly dire.