[6][7] He also developed a "pocket electrometer" that he used to amplify small electric charges to make them observable and measurable with an electroscope.

[10][11] Following the work of William Cullen in 1750 and Joseph Black in 1764, Cavallo was the first to carry out systematic experiments on refrigeration using the evaporation of volatile liquids, in 1781.

[13] In his Treatise on the Nature and Properties of Air (1781) he made "a judicious examination of contemporary work", discussing both the phlogiston theory of Joseph Priestley and the contrasting views of Antoine Lavoisier.

In June 1782, a paper of Cavallo's was read at the Royal Society, describing the first attempt to lift a hydrogen-filled balloon into the air.

His work influenced pioneer balloonists Jacques Charles, the Robert brothers, and Jean-Pierre Blanchard.