Combine 2 cups sugar, 1/2 cup corn syrup, 1/2 cup water, and a few grained salt. Stir until dissolved. Boil gently to soft ball stage (240 degrees). Beat 2 egg whites until stiff, but not dry. Gradually pour 1/4 of the syrup over the egg whites, beating constantly. Cook the remaining syrup to light crack stage (265 degrees).
Light crack test: Add several drops of mixture to cold water. Mixture will form a thin, firm ribbon which will bend when lifted out of water.
Beat remaining syrup into candy mixture, continue beating. When mixture holds its shape when dropped onto a greased cookie sheet. Swirl each piece with spoon to a peak.
Double cooking of syrup takes longer, but it's a failure-proof way to make fluffy Divinity. Use food coloring to color candy if desired.