Curley wears a "glove full of Vaseline" on one hand because "he's keepin' that hand soft for his wife," according to Candy. Because agricultural labor is physically demanding and hard on one's hands, the Vaseline will keep at least one of Curley's hands from getting chapped and rough, something he evidently expects his wife would dislike... -- excerpt from the novel Shrill Sound by Joseph McElroy Vaseline is used as a lubricant for tools and machinery. It also works as a skin protector for wearers who exercise or work with their hands/fingers. Curley's gloves are not rubber like those in today's world, but rather made out of animal skin - particularly sheepskin. At this time, people did not use gloves much except for farmers who needed protection for their hands while working in their fields. Sheep were used for their skins, which were then stripped off and turned into clothing, equipment, etc. There was no artificial material available in 1869 to replace the skin of animals.