ies. --Of Chemical Affinity, or Attraction of Composition.
--Examples of Composition and Decomposition.

CONVERSATION II.

ON LIGHT AND HEAT. 26

Light and Heat capable of being separated. --Dr. Herschel's
Experiments. --Phosphorescence. --Of Caloric. --Its two
Modifications. --Free Caloric. --Of the three different States of
Bodies, solid, fluid, and aeriform. --Dilatation of solid Bodies.
--Pyrometer. --Dilatation of Fluids. --Thermometer. --Dilatation of
Elastic Fluids. --Air Thermometer. --Equal Diffusion of Caloric.
--Cold a Negative Quality. --Professor Prevost's Theory of the
Radiation of Heat. --Professor Pictet's Experiments on the Reflexion
of Heat. --Mr. Leslie's Experiments on the Radiation of Heat.

CONVERSATION III.

CONTINUATION OF THE SUBJECT. 70

Of the different Power of Bodies to conduct Heat. --Attempt to
account for this Power. --Count Rumford's Theory of the
non-conducting Power of Fluids. --Phenomena of Boiling. --Of
Solution in general. --Solvent Power of Water. --Difference between
Solution and Mixture. --Solvent Power of Caloric. --Of Clouds, Rain,
Dr. Wells' theory of Dew, Evaporation, &c. --Influence of
Atmospherical Pressure on Evaporation. --Ignition.

CONVERSATION IV.

ON COMBINED CALORIC, COMPREHENDING SPECIFIC HEAT
AND LATENT HEAT. 122

Of Specific Heat. --Of the different Capacities of Bodies for Heat.
--Specific Heat not perceptible by the Senses. --How to be
ascertained. --Of Latent Heat. --Distinction between Latent and
Specific Heat. --Phenomena attending the Melting of Ice and the
Formation of Vapour. --Phenomena attending the Formation of Ice, and
the Condensation of Elastic Fluids. --Instances of Condensation, and
consequent Disengagement of Heat, produced by Mixtures, by the
Slaking of Lime. --General Remarks on Latent Heat. --Explanation of
the Phenomena of Ether boiling, and Water freezing, at the same
Temperature. --Of the Production of Cold by Evaporation.
--Calorimeter. --Meteorological Remarks.

CONVERSATION V.

ON THE CHEMICAL AGENCIES OF ELECTRICITY. 160

Of Positive and Negative Electricity. --Galvani's Discoveries.
--Voltaic Battery. --Electrical Machine. --Theory of Voltaic
Excitement.

CONVERSATION VI.

ON OXYGEN AND NITROGEN. 181