APPENDIX. _Abstract of De la Roche and Berard’s essay on the specific heat of gases_ 268 ---- _Dulong and Petit’s essays, On the expansion of air, mercury, glass, iron, copper, and platina, by heat_ 272 _On the capacities of certain bodies, for heat_ 274 _On the laws of refrigeration_ 277 _On the specific heats of certain bodies_ 280 _Remarks on the above essays_ 282 _New Table of the forces of vapours_ 298 _Table of the expansion of air, and the force of aqueous and ætherial vapour, adapted to atmospheric temperatures_ 299 _Applications of the above table_ 300 _Formulæ for determining the proportions of combustible gases, in mixtures_ 305 _Heat produced by the combustion of gases_ 309 _Absorption of gases by water_ 309 _Fluoric acid--deutoxide of hydrogen_ 311 _Muriatic acid--oxymuriatic acid_ 313 _Nitric acid--compounds of azote and oxygen_ 315 _On ammonia_ 328 _Decomposition of ammonia by nitrous oxide_ 330 ---- ---- ---- _by nitrous gas and oxygen_ 332 _Volume of gases from the decomposition of ammonia_ 335 _Decomposition of ammonia by a red heat_ 335 _Decomposition of ammonia by oxymuriatic acid_335 _Sulphuret of Carbon_ 338 _Potassium, Sodium, &c._ 340 _Alum_ 341 _New table of the relative weights of atoms._ 352 ADDENDA. _Steel; mixed gases; expansion of liquids by heat_ 354 NEW SYSTEM OF _CHEMICAL PHILOSOPHY_. CHAP. V. SECTION 13. METALLIC OXIDES. All the metals are disposed to combine with oxygen, but the combination is effected more easily with some than with others; the compound is usually called an _oxide_, but in some instances it is also called an _acid_. The same metal combines with one, two, or perhaps more atoms of oxygen, forming compounds which may be distinguished according to Dr. Thomson, by the terms _protoxide_, _deutoxide_, _tritoxide_, &c.