who pioneered a method of using hydrogen in balloons to produce lift
Following Robert Boyle's Boyle's Law which had been published in 1662, and Henry Cavendish's 1766 work on hydrogen, Joseph Black proposed that if the gaseous element filled a balloon, the inflated object could rise up into the air. Jacques Charles, whose study of gases led to his namesake law of volumes, had studied the works of Cavendish, Black, and Tiberius Cavallo, and also thought that hydrogen could lift a balloon.