18. An Account of some New Experiments on the Fluoric Compounds; with some Observations on other objects of Chemical Enquiry. _February 13, 1814._ 19. Some Experiments and Observations on a new Substance, which becomes a Violet-coloured Gas by heat. _January 20, 1814._ 20. Further Experiments and Observations on Iodine. _Read June 16, 1814._ 21. Some Experiments on the Combustion of the Diamond, and other Carbonaceous Substances. _June 23, 1814._ 22. Some Experiments and Observations on the Colours used in Painting by the Ancients. _February 23, 1815._ 23. Some Experiments on a solid Compound of Iodine and Oxygen, and on its Chemical Agencies. _April 20, 1815._ 24. On the Action of Acid upon the Salts usually called _Hyper-Oxymuriates_, and on the Gases produced from them. _May 4, 1815._ 25. On the _Fire-damp_ of Coal Mines, and on methods of lighting the Mine, so as to prevent Explosion. _November 19, 1815._ 26. An Account of an Invention for giving Light in Explosive Mixtures of _Fire-damp_ in Coal Mines, by consuming the Fire-damp. _January 11, 1816._ 27. Further Experiments on the Combustion of Explosive Mixtures confined by Wire Gauze, with some Observations on Flame. _January 25, 1816._ 28. Some Researches on Flame. _January 16, 1817._ 29. Some New Experiments and Observations on the Combustion of Gaseous Mixtures; with an account of a method of preserving a continued Light in Mixtures of inflammable Gases and Air, without Flame. _Read January 23, 1817._ *** _For the preceding five papers, the Rumford Medals were awarded to him._ 30. On the fallacy of Experiments in which Water is said to have been formed by the decomposition of Chlorine. _February 12, 1818._ 31. New Experiments on some of the combinations of Phosphorus. _April 9, 1818._ 32. Some Observations on the formation of Mists in particular situations. _February 25, 1819._ 33. On the Magnetic Phenomena produced by Electricity. _November 16, 1820._ 34. Some Observations and Experiments on the Papyri found in the ruins of Herculaneum. _March 15, 1821._ 35. Further Researches on the Magnetic Phenomena produced by Electricity; with some new Experiments on the properties of Electrified bodies, in their relations to conducting powers and temperature. _July 5, 1821._ 36. On the Electrical Phenomena exhibited _in vacuo_. _December 20, 1821._ 37. On the state of Water and Aëriform matter in cavities found in certain Crystals. _Read June 13, 1822._ 38. On a new Phenomenon of Electro-Magnetism. _March 6, 1823._ 39. On the application of Liquids formed by the condensation of Gases, as mechanical Agents. _April 17, 1823._ 40. On the changes of volume produced in Gases, in different states of density, by Heat. _May 1, 1823._