Category: Science - Physics
The instrument which has so vastly extended our knowledge of the Universe, which has enabled us to acquire observations of remarkable precision, and supplied the materials for many sublime speculations in Astronomy, was invented early in the seventeenth century. Apart from its...
The instrument which has so vastly extended our knowledge of the Universe, which has enabled us to acquire observations of remarkable precision, and supplied the materials for m...
4. CHAPTER II.The number of large telescopes having so greatly increased in recent years, and there being every prospect that the demand for such instruments will continue, it may be well to...
5. CHAPTER III.Choice of Telescopes.—Refractors and Reflectors.—Observer’s Aims.—Testing Telescopes.—Mounting.—Eyepieces.—Requisite Powers.—Overstating Powers.—Method of finding the Power.—Fie...
6. CHAPTER IV._Preparation._—An observer in commencing work in any department of astronomy will find it a very great assistance to his progress if he carefully reads and digests all that has...
7. CHAPTER V.Solar Observations.—Early notices of Spots.—Difficulties of the old observers.—Small instruments useful.—Tinted glass.—Solar Diagonal.—Structure of a Spot.—Methods of Drawing.—A...
8. CHAPTER VI.Attractive aspect of the Moon.—Absence of air and water.—Only one Hemisphere visible.—Earthshine.—Telescopic observations of the lunar surface.—Eclipses.—Lunar changes.—Formatio...
9. CHAPTER VII.Supposed planet, “Vulcan.”—Visibility of Mercury.—Period &c.—Elongations.—Amateur’s first view.—Phases.—Atmosphere of Mercury.—Telescopic observations.—Schiaparelli’s results.—O...
10. CHAPTER VIII.Beauty of Venus.—Brilliancy.—Period &c.—Venus as a telescopic object.—Surface-markings on the planet.—Rotation-period.—Faintness of the markings.—Twilight on Venus.—Alleged Sate...
11. CHAPTER IX.Appearance of the planet.—Period &c.—Phase.—Surface Configuration.—Charts and Nomenclature of Mars.—Discovery of two Satellites and of Canal-shaped markings.—Summary of Observat...
12. CHAPTER X._Number._—These bodies, also called minor planets, and, formerly, asteroids, comprise a very numerous class, and they are extremely small, being quite invisible to the naked eye...
13. CHAPTER XI.An interesting Object.—Brightness and Position.—Period &c.—Belts and Spots on the Planet.—Observations of Hooke, Cassini, and others.—The “Ellipse” of 1869-70.—The Red Spot, its...
14. CHAPTER XII.Apparent lustre.—Grand spectacle afforded by the Rings.—Period &c.—“Square-shouldered” aspect.—Early Observations.—Belts and Spots on the Planet.—Rotation-Period.—The Rings.—Div...
15. CHAPTER XIII.Discovery of Uranus.—Mistaken for a Comet.—True character revealed.—Period &c.—Observations.—Belts on Uranus.—Further Observations required.—The Satellites.—Discovery of Neptune...
16. CHAPTER XIV.Ideas concerning Comets.—Appearance.—Large number visible.—Nature of Apparition.—Tenuity of Comets.—Differences of Orbit.—Discoveries of Comets.—Large Comets.—Periodical Comets....
17. CHAPTER XV.Ancient ideas concerning Meteors.—Meteoric Apparitions.—Radiation of Meteors.—Identity of Meteors and Comets.—Aerolites.—Fireballs.—Differences of Motion.—Nomenclature of Meteor...
18. CHAPTER XVI.Sidereal Work.—Greek alphabet.—Learning the Names of the Stars.—The Constellation figures.—Means of Measurement.—Dividing power.—Number of Stars.—Magnitudes.—The Milky Way.—Scin...
19. CHAPTER XVII.Distinction.—Large number of Nebulæ and Clusters visible.—Varieties of form and grouping.—Distribution.—Early Observations.—Variable Nebulæ.—Nebulous Stars.—The Magellanic Cloud...