2 Words to use with hub

By voice and whip I turned my cattle down the stream to the south, and for a mile I drove in water half-hub deep.

A solid shot struck No. 5 gun on the hub, killing Cannoneer No. 2, who was thumbing the vent, and filling No. 1 gunner with splinters of iron, whirling him into eternity amid a fountain of dirt and flying hub-tires.

2 Words to use with  hub