Inserted after p. 344: "Fac-simile of the erroneous title-page prefixed to the separate copies of Mr. Cavendish's 'Experiments on air,' read before the Royal society, January 15, 1784." Appendix: No. I. List of the works of Denys Papin. No. II. Historical note on the discovery of the theory of the composition of water. By the Right Hon. Henry Lord Brougham ... No. III. Summary of the history of the progress towards the discovery of the composition of water, and of the discovery itself. Includes index.