Electricity

Again, The concretion of Ice will not endure a dry attrition without liquation; for if it be rubbed long with a cloth, it melteth. But Crystal will calefie unto electricity, that is, a power to attract straws or light bodies, and convert the needle freely placed. Which is a declarement of very different parts, wherein we shall not inlarge, as having discoursed concerning such bodies in the Chap. of Electricks.

49 The Nature of the Study of the Cosmos . . . . . . . . . . . . . . . 50 The special Requirements of the present Age . . . . . . . . . . . . 53 Limits and Method of Exposition of the Physical Description of the Universe . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 Considerations on the terms Physiology and Physics . . . . . . . . .58 Physical Geography . . . . . . . . . . . . . . . . . . . . . . . . 59 Celestial Phenomena . . . . . . . . . . . . . . . . . . . . . . . . 63 The Natural Philosophy of the Ancients directed more to Celestial than to Terrestrial Phenomena . . . . . . . . . . . . . . . . .65 The able Treatises of Varenius and Carl Ritter . . . . . . . . .66, 67 Signification of the Word Cosmos . . . . . . . . . . . . . . . . 68-70 The Domain embraced by Cosmography . . . . . . . . . . . . . . . . 71 Empiricism and Experiments . . . . . . . . . . . . . . . . . . . . 74 The Process of Reason and Induction . . . . . . . . . . . . . . . .77 p 14 GENERAL REVIEW OF NATURAL PHENOMENA. Connection between the Material and the Ideal World . . . . . . . . 80 Delineation of Nature . . . . . . . . . . . . . . . . . . . . . . . 82 Celestial Phenomena . . . . . . . . . . . . . . . . . . . . . . . . 83 Sidereal Systems . . . . . . . . . . . . . . . . . . . . . . . . . 89 Planetary Systems . . . . . . . . . . . . . . . . . . . . . . . . .90 Comets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 Aerolites . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111 Zodiacal Light . . . . . . . . . . . . . . . . . . . . . . . . . . 137 Translatory Motion of the Solar System . . . . . . . . . . . . . . 145 The Milky Way . . . . . . . . . . . . . . . . . . . . . . . . . . .150 Starless Openings . . . . . . . . . . . . . . . . . . . . . . . 152 Terrestrial Phenomena . . . . . . . . . . . . . . . . . . . . . . .154 Geographical Distribution . . . . . . . . . . . . . . . . . . . . .161 Figure of the Earth . . . . . . . . . . . . . . . . . . . . . . . .163 Density of the Earth . . . . . . . . . . . . . . . . . . . . . . . 169 Internal Heat of the Earth . . . . . . . . . . . . . . . . . . . . 172 Mean Temperature of the Earth . . . . . . . . . . . . . . . . . . .175 Terrestrial Magnetism . . . . . . . . . . . . . . . . . . . . . . 177 Magnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . . .183 Aurora Borealis . . . . . . . . . . . . . . . . . . . .. . . . . .193 Geognostic Phenomena . . . . . . . . . . . . . . . . . . . . . . . 202 Earthquakes . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 Gaseous Emanations . . . . . . . . . . . . . . . . . . . . . . . . 207 Hot Springs . . . . . . . . . . . . . . . . . . . . . . . . . . . .221 Salses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224 Volcanoes . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227 Rocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .247 Palaeontology . . . . . . . . . . . . . . . . . . . . . . . . . . .270 Geognostic Periods . . . . . . . . . . . . . . . . . . . . . . . . 286 Physical Geography . . . . . . . . . . . . . . . . . . . . . . . . 287 Meteorology . . . . . . . . . . . . . . . . . . . . . . . . . . . .311 Atmospheric Pressure . . . . . . . . . . . . . . . . . . . . . . . 315 Climatology . . . . . . . . . . . . . . . . . . . . . . . . . . . .317 The Snow-line . . . . . . . . . . . . . . . . . . . . . . . . . . .329 Hygrometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332 Atmospheric Electricity . . . . . . . . . . . . . . . . . . . . . .335 Organic Life . . . . . . . . . . . . . . . . . . . . . . . . . . . 339 Motion in Plants . . . . . . . . . . . . . . . . . . . . . . . . . 341 Universality of Animal Life . . . . . . . . . . . . . . . . . . . .342 Geography of Plants and Animals . . . . . . . . . . . . . . . . . .346 Floras of different Countries . . . . . . . . . . . . . . . . . . .350 Man . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .352 Races . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .353 Language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 357 Conclusion of the Subject . . . . . . . . . . . . . . . . . . . . .359

g. Liquid and aeriform envelopes of the solid surface of our planet. Distribution of heat in both. The sea. The tides. Currents and their effects -- p. 301-311. h. The atmosphere. Its chemical composition. Fluctuations in its density. Law of the direction of the winds. Mean temperature. Enumeration of the causes which tend to raise and lower the temperature. Continental and insular climates. East and west coasts. Cause of the curvature of the isothermal lines. Limits of perpetual snow. Quantity of vapor. Electricity in the atmosphere. Forms of the clouds -- p. 311-339. i. Separation of inorganic terrestrial life from the geography of vital organisms; the geography of vegetables and animals. Physical gradations of the human race -- p. 339-359. Special Analysis of the Delineation of Nature, including References to the Subjects treated of in the Notes. I. Celestial Portion of the Cosmos . . . . . . . . . . . . . . . . . p. 83-154

eousness consists with — I am very far indeed from saying that it is generally accompanied by — a heart of impenetrable hardness, an intellect of the utmost tenuity, and a life of complete selfishness. I have known distinguished fathers and mothers in our Christian Israel whose presence was like mildew upon flowers, and who sent you away with the feeling of having been defrauded of half your vital electricity. They were fathers that begot nothing but their own vapid arrogance, and mo- thers that suckled nothing more tender than their own strapping self-conceit. For there is nothing humanizing — nothing elevating — in personal devo- tion, after you reach a certain stage of culture in the race. It is well for me when my will is purely sensual or devilish — when it insists upon over- riding everything to compass a momentary grati- fication— when in short I am an infant in culture and manifest the disposition of an infant — then it is well for me to obey the will of a superior. Devotion then is both profitable and honorable. And in the earliest periods of human history accordingly we see it most abounding.

out to us, and which has so long furnished the staple spiritual commodity of the old theologj. But I vehemently discredit the prospect of any positive good. Man's true good never comes from without him, but only from the depths of divinity within him, and whatever tends to divert his atten- tion from this truth, and fix it on Mahommedan paradises, and salvation through electricity, claims his most vindictive anathema. Above all, a spirit- ual life which feels itself depleted by the diligent prosecution of the natural one, which is actually interested to invade the latter, and persuade good sound flesh and blood to barter its savory cakes and ale for trite and faded sentimentalities, is a life which every reasonable person may safely scout as unworthy his aspiration.

“ On the whole I am led to regard these so-called ‘ spirits’ rather as so many vermin revealing themselves in the tumble-down walls of our old theological hostelry, than as any very saintly and sweet persons, whose ac- quaintance it were edifying or even comfortable to make. I hope their pale activity — their bloodless and ghastly vivacity — may do indirect good by promoting a general disgust for the abject personal gossip which they deal out to us, and which has so long furnished the staple spiritual commodity of the old theology. But I vehe- mently discredit the prospect of any positive good. Man’s true good never comes from without him, but only from the depths of divinity within him, and whatever tends to divert his attention from this truth, and fix it on Ma- hommedan paradises, and salvation through electricity, claims his most vindictive anathema. Above all, a spi- Digitized by Google APPENDIX

SECTION XXVIII. Common or Static Electricity, or Electricity of Tension—A Dual Power—Methods of exciting it—Attraction and Repulsion—Conduction—Electrics and Non-electrics—Induction—Dielectrics—Tension—Law of the Electric Force—Distribution—Laws of Distribution—Heat of Electricity—Electrical Light and its Spectrum—Velocity—Atmospheric Electricity—Its cause—Electric Clouds—Violent effects of Lightning—Back Stroke—Electric Glow—Phosphorescence 282 SECTION XXIX. Voltaic Electricity—The Voltaic Battery—Intensity—Quantity—Static Electricity, and Electricity in Motion—Luminous Effects—Mr. Grove on the Electric Arc and Light—Decomposition of Water—Formation of Crystals by Voltaic Electricity—Photo-galvanic Engraving—Conduction—Heat of Voltaic Electricity—Electric Fish 297 SECTION XXX. Discovery of Electro-magnetism—Deflection of the Magnetic Needle by a Current of Electricity—Direction of the Force—Rotatory Motion by Electricity—Rotation of a Wire and a Magnet—Rotation of a Magnet about its Axis—Of Mercury and Water—Electro-Magnetic Cylinder or Helix—Suspension of a Needle in a Helix—Electro-Magnetic Induction—Temporary Magnets—The Galvanometer 312 SECTION XXXI. Electro-Dynamics—Reciprocal Action of Electric Currents—Identity of Electro-Dynamic Cylinders and Magnets—Differences between the Action of Voltaic Electricity and Electricity of Tension—Effects of a Voltaic Current—Ampère’s Theory—Dr. Faraday’s Experiment of Electrifying and Magnetising a Ray of Light

316 SECTION XXXII. Magneto-Electricity—Volta-Electric Induction—Magneto-Electric Induction—Identity in the Action of Electricity and Magnetism—Description of a Magneto-Electric Apparatus and its Effects—Identity of Magnetism and Electricity—The Submarine Telegraph 322 SECTION XXXIII. Electricity produced by Rotation—Direction of the Currents—Electricity from the Rotation of a Magnet—M. Arago’s Experiment explained—Rotation of a Plate of Iron between the Poles of a Magnet—Relation of Substances to Magnets of three Kinds—Thermo-Electricity 330 SECTION XXXIV. Magnetism a Dual Power—Antithetic Character of Paramagnetism and Diamagnetism—The Earth Paramagnetic—Properties of Paramagnetic Bodies—Polarity—Induction—Lines of Magnetic Force—Currents of Electricity induced by them—Proved to be Closed Curves—Analogy and Identity of Electricity and Magnetism—Terrestrial Magnetism—Mean Values of the Three Magnetic Elements—Their Variations in Double Progression proved to consist of Two Superposed Variations—Discovery of the Periodicity of the Magnetic Storms—The Decennial Period of the Magnetic Elements the same with that of the Solar Spots—Magnetism of the Atmosphere—Diamagnetism—Action of Electro-Magnetism on Paramagnetic, Diamagnetic Bodies, and on Copper, very different—Proof of Diamagnetic Polarity and Induction—Magnecrystallic Action—Effects of Compression, Heat, and Cleavage on Magnetic Bodies—Mutual Dependence of Light, Heat, Electricity, &c. &c.—The Conservation of Force and the Permanency of Matter Primary Laws of Nature—Definition of Gravity not according to that Law—Gravity only the Residual Force of a Universal Power—Magnetism of the Ethereal Medium

In consequence of the relations already mentioned in the mean motions and mean longitudes of the first three satellites, they never can be all eclipsed at the same time: for, when the second and third are in one direction, the first is in the opposite direction; consequently, when the first is eclipsed, the other two must be between the sun and Jupiter. The instant of the beginning or end of an eclipse of a satellite marks the same instant of absolute time to all the inhabitants of the earth; therefore, the time of these eclipses observed by a traveller, when compared with the time of the eclipse computed for Greenwich, or any other fixed meridian (N. 95), gives the difference of the meridians in time, and, consequently, the longitude of the place of observation. The longitude is determined with extreme precision whenever it is possible to convey the time instantaneously by means of electricity from one place to another, since it obviates the errors of clocks and chronometers. The eclipses of Jupiter’s satellites have been the means of a discovery which, though not so immediately applicable to the wants of man, unfolds one of the properties of light—that medium without whose cheering influence all the beauties of the creation would have been to us a blank.

The various hypotheses that have been formed as to the nature and action of the forces which unite the particles of matter, have been successively given up as science advanced, and now nothing decisive has been attained, although Professor Mossotti, of Pisa, by a very able analysis, has endeavoured to prove the identity of the cohesive force with gravitation. As the particles of material bodies are not in actual contact, he supposes that each is surrounded by an atmosphere of the ethereal medium, which he conceives to be electricity; moreover he assumes that the atoms of the medium repel one another, that the particles of matter also repel one another, but with less intensity, and that there is a mutual attraction between the particles of matter and the atoms of the medium, forces which are assumed to vary inversely as the square of the distance.