Chapter VI: Heat--Solar and Terrestrial

Solar and Terrestrial Heat--Position of the Earth
in the Solar System--Heat and Light associated in
the Sunbeam--Transparency of Bodies to Heat--Heating
Powers of the Coloured Rays of the Spectrum--Undulatory
Theory--Conducting Property of the Earth’s
Crust--Convection--Radiation--Action of the Atmosphere on
Heat Rays--Peculiar Heat Rays--Absorption and Radiation
of Heat by dissimilar Bodies--Changes in the Constitution
of Solar Beam--Differences between Transmitted and
Reflected Solar Heat--Phenomena of Dew--Action of
Solar Heat of the Ocean--Circulation of Heat by the
Atmosphere and the Ocean--Heat of the Earth--Mean
Temperature--Central Heat--Constant Radiation of Heat Rays
from all Bodies--Thermography--Action of Heat on Molecular
Arrangements--Sources of Terrestrial Heat--Latent Heat
of Bodies--Animal Heat--Eremacausis--Spheroidal State
Cold--Condensation--Freezing--Theories of Heat--Natural
Phenomena--and Philosophical Conclusion 62

CHAPTER VII.

LIGHT.

Theories of the Nature of Light--Hypotheses
of Newton and Huygens--Sources of Light--The
Sun--Velocity of Light--Transparency--Dark
Lines of the Spectrum--Absorption of
Light--Colour--Prismatic Analysis--Rays of the
Spectrum--Rainbow--Diffraction--Interference--Goethe’s
Theory--Polarisation--Magnetisation of Light--Vision--The
Eye--Analogy--Sound and Light--Influence of Light on
Animals and Vegetables--Phosphorescence arising from
several Causes--Artificial Light--Its Colour dependent on
Matter 118

CHAPTER VIII.

ACTINISM--CHEMICAL RADIATIONS.

The Sun-ray and its Powers--Darkening of
Horn Silver--Niepce’s Discovery--Prismatic
Spectrum--Refrangibility of Light, Heat, and
Actinism--Daguerre’s Discovery--Photography--Chemical
Effects produced by Solar Radiations--Absorption of
Actinism--Phenomena of the Daguerreotype--Chemical
Change produced upon all Bodies--Power of Matter to
restore its Condition--Light protects from Chemical
Change--Photographs taken in Darkness--Chemical Effects
of Light on organized Forms--Chemical Effects of Solar
Heat--Influence of Actinism on Electricity--Radiations in
Darkness--Moser’s Discoveries, &c. 166

CHAPTER IX.

ELECTRICITY.

Discovery of Electrical Force--Diffused through all
Matter--What is Electricity?--Theories--Frictional
Electricity--Conducting Power of Bodies--Hypothesis
of two Fluids--Electrical Images--Galvanic
Electricity--Effects on Animals--Chemistry of Galvanic
Battery--Electricity of a Drop of Water--Electro-chemical
Action--Electrical Currents--Thermo-Electricity--Animal
Electricity--Gymnotus--Torpedo--Atmospheric
Electricity--Lightning Conductors--Earth’s Magnetism due
to Electrical Currents--Influence on Vitality--Animal and
Vegetable Development--Terrestrial Currents--Electricity
of Mineral Veins--Electrotype--Influence of Heat, Light,
and Actinism on Electrical Phenomena 193

CHAPTER X.

MAGNETISM.

Magnetic Iron--Knowledge of, by the Ancients--Artificial
Magnets--Electro-Magnets--Electro-Magnetism--Magneto-
Electricity--Theories of Magnetism--The Magnetic
Power of soft Iron and Steel--Influence of Heat
on Magnetism--Terrestrial Magnetism--Declination
of the Compass-needle--Variation of the
Earth’s Magnetism--Magnetic Poles--Hansteen’s
Speculations--Monthly and Diurnal Variation--Dip and
Intensity--Thermo-Magnetism--Aurora Borealis--Magnetic
Storms--Magnetic conditions of Matter--Diamagnetism, &c. 235

CHAPTER XI.

CHEMICAL FORCES.

Nature’s Chemistry--Changes produced by Chemical
Combination--Atomic Constitution of Bodies--Laws
of Combination--Combining Equivalents--Elective
Affinity--Chemical Decomposition--Compound Character
of Chemical Phenomena--Catalysis or action of
Presence--Transformation of Organic Bodies--Organic
Chemistry--Constancy of Combining Proportions--The Law of
Volumes, the Law of Substitutions, Isomeric States, &c. 270

CHAPTER XII.

CHEMICAL PHENOMENA.

Water--Its Constituents--Oxygen--Hydrogen--Peroxide
of Hydrogen--Physical Property of
Water--Ice--Sea Water--Chlorine--Muriatic
Acid--Iodine--Bromine--Compounds of Hydrogen
with Carbon--Combustion--Flame--Safety
Lamp--Respiration--Animal Heat--The Atmosphere--Carbonic
Acid--Influence of Plants on the Air--Chemical Phenomena
of Vegetation--Compounds of Nitrogen--Mineral Kingdom, &c.
&c. 295

CHAPTER XIII.

TIME.--GEOLOGICAL PHENOMENA.

Time, an element in Nature’s Operations--Geological
Science--Its Facts and Inferences--Nebular Hypothesis
applied--Primary Formations--Plutonic and Metamorphic
Rocks--Transition Series--Palæozoic Rocks--Commencement
of Organic Arrangements--Existence of Phosphoric
Acid in Plutonic Rocks--Fossil Remains--Coal
Formation--Sandstones--Tertiary Formations--Eocene,
Miocene, and Pliocene Formations--Progressive changes
now apparent--General Conclusions--Physics applied in
explanation 332

CHAPTER XIV.

PHENOMENA OF VEGETABLE LIFE.

Psychology of Flowers--Progress of Matter
towards Organization--Vital Force--Spontaneous
Generation--The Vegetable Cell--Simplest Development
of Organization--The Crystal and the Cell--Primitive
Germ--Progress of Vegetation--Influence of
Light--Morphology--Germination--Production of Woody
Fibre--Leaves--Chlorophylle--Decomposition of
Carbonic Acid--Influence of Light, Heat, and Actinism
on the Phenomena of Vegetable Life--Flowers and
Fruits--Etiolation--Changes in the Sun’s Rays with the
Seasons--Distribution of Plants--Electrical and Combined
Physical Powers 357

CHAPTER XV.

PHENOMENA OF ANIMAL LIFE.

Distinction between the Kingdoms
of Nature--Progress of Animal
Life--Sponges--Polypes--Infusoria--Animalcula--Phosphorescent
Animals--Annelidans--Myriapoda--Animal
Metamorphoses--Fishes--Birds--Mammalia--Nervous
System--Animal Electricity--Chemical Influences--Influence
of Light on Animal Life--Animal Heat--Mechanical
Action--Nervous Excitement--Man and the Animal Races, &c. 383

CHAPTER XVI.

GENERAL CONCLUSIONS.

The Changes produced on Physical Phenomena by the Movement
of the Solar System considered--Exertion of the Physical
Forces through the Celestial Spaces--The Balance of
Powers--Varieties of Matter--Extension of Matter--Theory
of Nonentity--A Material Creation an indisputable
fact--Advantages of the Study of Science--Conclusion 403

INDEX. 413

BOHN’S BOOKS.

TRANSCRIBER’S NOTE.