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A Primary Astronomy . *% V *> v- ^ V* "> ^ c ' -0' w X i5 u «K A^' '^A * <£ %. '" '/ ft \v SIXINCHACHROMATIG TELESCOPE MADEBYMR.HENRYFITZ OFTHE CITY OF NEW YORK, AND MOUNTED EQUATORIALLY BY MESSRS. GREGG fy RUPP OF THE SAME CITY. IT IS 8 FEET IN LENGTH,^ T HE TOTAL COST OF THE INSTRUMENT ABQUT$IOOO. IT SHOW< HE MOON ^PLANETS WITH GREAT SHARPNESS.THE 5TH. £6TH. STARS IN THE TRAPEZIUMvOF 9, ORIONIS.& SEPARATES E, ARIETIS, 36ANDR0MEDAE, AND OTHER CLOSf STARS OF THE SAME CLASS. IT IS NOW EJECTED IN THE OBSERVATORY OF LEWIS M. RUTHERFORD, ESQ. INTHE CITY OF NEW YORK. H&cfli. cJ^jAix-ty^ i-L.(?n PRIMARY ASTRONOMY, FOR SCHOOLS AND FAMILIES: ADAPTED TO THE CAPACITY OF YOUTH, AND ILLUSTRATED BY NEARLY TWO HUNDRED ENGRAVINGS. BY HIRAM MATTISON, PROFESSOR OF NATURAL PHILOSOPHY AND ASTRONOMY IN THE FALLEY SEMINARY I AUTHOR OF THE ELEMENTARY ASTRONOMY, ASTRONOMICAL MAPS, ETC. ETC. ^ NEW YORK: HUNTINGTON AND SAVAGE, MASON AND LAW, 23 PARK ROW, (Opposite the Astor House.) 1851. zL * & Entered according to Act of Congress, in the year 185 1, By HIRAM MATTISON, In the Clerk's Office of the District Court for the Southern District of New York. 0* Vy L Stereotyi)ed by RICHARD C. VALENTINE, 45 Gold-st., New York. k CONTENTS. PART FIRST. PRELIMINARY OBSERVATIONS AND DEFINITIONS. PAGE I. History of Astronomy 5 II. The Modern, or Copernican System 9 IIL Geometrical Definitions 14 IV. Of Lines and Angles 18 V. Of the Circle and the Ellipse 20 VL The Terrestrial and Celestial Spheres 24 PART SECOND. OF THE SOLAR SYSTEM. VII. Bodies that compose the System 31 VIII. Names of the Planets, Signs, <fec. 33 IX. Distances of the Planets from the Sun 38 X. Light and Heat of the several Planets 40 XI. Magnitude, Density, and Gravitation of the Planets 42 XII. Revolution of the Planets around the Sun 46 XIII. Aspects, Sidereal and Synodic Revolutions, &c 50 XIV. Direct and Retrograde Motions, Planets Stationary, &c... 53 XV. Diurnal Revolutions of the Planets, Time, &c 51 XVL The Ecliptic, Zodiac, Signs, Longitude, &c 63 XVII. Form and Position of the Planetary Orbits, Nodes, &c. ... 69 XVIII. Of Transits 73 XIX. The Sun's apparent Motions, the Seasons, <fec 76 XX. Seasons of the different Planets, Telescopic Views, &c 82 XXI. Telescopic Views of the Planets continued 87 XXII. Of the Secondary Planets. 93 XXIIL Revolution of the Moon around the Earth 96 XXIV. The Moon's Changes 101 XXV. Day and Night, Seasons, <fec, of the Moon 106 XXVL Eclipses of the Sun 113 XXVII. Eclipses of the Moon 120 XXVIII. Satellites of Jupiter, Eclipses, <fec 123 XXIX. Satellites of Saturn, Herschel, and Neptune 128 XXX. Of the Tides 131 XXXI. Of Spring and Neap Tides 135 SUGGESTIONS TO TEACHERS, ETC. XXXII Of Comets 138 XXXIII. Of the Sun 145 XXXIV. General Remarks upon the Solar System.... 152 PART THIRD. OF THE SIDEREAL HEAVENS. XXXV. The Fixed Stars—their Number, Distances, &o 155 XXXVI. Double, Variable, and Temporary Stars 159 XXXVII. Clusters of Stars and Nebulae 161 XXXVIII. Of the Atmosphere, Winds, Clouds, Storms, &c 165 SUGGESTIONS TO TEACHERS AID STUDENTS. 1. The coarse print should generally be committed to memory, as an answer to the questions. 2. The fine print and the cuts should be carefully studied ; and the student should be prepared, if called upon, to make drawings similar to those found in the lesson upon the blackboard. 3. In studying the illustrations, the pupil should generally imagine himself to be looking South—the top of the book being North ; the bottom South ; the left hand East ; and the right hand West. 4. The teacher should call upon the several members of the class, in succession, to sketch the diagrams as they occur in the lesson, and to show how they illustrate the point under considera- tion—this explanation being in all cases extemporaneous. 5. The Pronunciation, Definition, and Derivation of terms should receive special attention ; and to facilitate such inquiries, important words are not only pronounced and defined, but are traced to their original source. 6. Finally, whenever practicable, let the objects or phenomena described in the lessons be looked up and observed as they really appear in nature. This will invest the subject with new interest, and will excite in the mind of the student a desire to know more of this most wonderful and most sublime of all human studies. New York, January, 1851. — PRIMARY ASTRONOMY, PART I. PRELIMINARY OBSERVATIONS AND DEFINITIONS. LESSON I. HISTORY OF ASTRONOMY. 1. Question.— What is Astronomy ? Answer.—It is the science of the Heavenly Bodies the Sun, Moon, Planets, Comets, and Stars. 2. What does it teach respecting these bodies ? Their names, distances, magnitudes, and motions, and the causes of Day and Night, the Seasons, Eclipses, Tides, and various other phenomena.* 3. Was Astronomy known to the ancients? It was; and was taught in Egypt, Chaldea, India, China, and Greece long before the birth of Christ. 4. What was the occupation of the first Astronomers ? They were shepherds and herdsmen. 5. By what were they led to this study? By observing the movements of the sun, moon, and stars, while watching their flocks from year to year in the open fields, f * Phe-nom'-e-na, appearances ; things presented to the eye, or events seen to take place. The singular of this term is Phe-nom-e-non. f Norton's Elementary Treatise, page 2. 1* PRIMARY ASTRONOMY. ANCIENT ASTRONOMERS OBSERVING THE HEAVENS. 6. Where do modern Astronomers make their observations 1 In what are called Observatories. the heavens. The [An observatory is a place erected for the purpose of observing Mitchel on Mount most celebrated in this country is the one erected by Professor Philadelphia, Adams, Cincinnati. Besides this, there is one at Washington, one at to erect one on one at Cambridge, Mass., &c. An effort is now being made (1850) M. Brooklyn Hights, Long Island. A good private observatory, owned by Lewis Rutherford, Esq., may be seen in the rear of his residence, corner of Second Avenue and Eleventh street, New York City.] BR. DICK'S OBSERVATORY, NEAR DUNDEE, SCOTLAND. 7, What other advantage have modern Astronomers ? They are assisted by many useful instruments, the most important of which is the Telescope* * From the Greek tele, at a distance, and skopeo, to see. PRIMARY ASTROXOMY. [This is a picture of the Great Refracting MODERN ASTRONOMERS USING Telescope of the Cincinnati Observatory. It is A TELESCOPE. reduced and copied from a cut in the first num- ber of the Sidereal Messenger* July, 1846. The original (which is an enlargement of a daguerre- otype) is exceedingly accurate and beautiful, and our artist has given us an exact miniature of it in the page before you. This Telescope has an object-glass (placed in the top of the tube toward the objects to be seen) which is twelve inches in diameter. The tube, which is seventeen feet long, and the Telescope, alone cost $9,437. It was made at Munich, in Germany.] §. What did the ancients think of the form of the earth ? Instead of a globe inhabited on all sides, they believed it to be a plane, inhabited on one side only. 9. What did they think of her motions, and those of the heavenly bodies ? They believed the earth to be at rest in the center of the universe, and that the sun, moon, and stars actually revolved around her, from east to west, as they appear to do, every twenty-four hours. [It is by no means strange that the ancients were thus deceived by appearances. Seeing but a small portion of the earth at any one time, they were easily misled in re- gard to its form ; and having no idea of its revolution, it was natural to suppose that the apparent daily revolution of the heavenly bodies westward was real. In the same manner persons often attribute their own motions to bodies that are at rest, especially when carried swiftly forward without any apparent cause (as when one travels in a steamboat or railway car), and when for a time they forget their own motions.] 10. What other notions had the ancients in respect to the figure of the earth ? That it was longest from east to west. [They observed that traveling east or west had no effect upon the apparent position of the stars, while going north and south did. Hence the conclusion that the earth was narrowest north and south. This erroneous idea was the origin of our modern terms, latitude and longitude, the last of which means length, and the former I breadth.'] 11. What was the ancient system of Astronomy called, and why? 8 PRIMARY ASTRONOMY. The Ptolemaic* Theory, from Ptolemy,f an Egyptian philosopher, who nourished in the second century of the Christian era. [1. The word Ptolemy was a common name for the successive Egyptian princes, as Pharaoh:): was for the kings of Egypt in the days of Moses. PTOLEMAIC THEORY OF THE STRUCTURE OF THE UNIVERSE. 2. The ancients supposed the earth to be surrounded by eight crystalline arches or spheres, one within the other, in which the sun, moon, and stars were set. In this way they accounted for their not falling down upon the earth, while the light of the most distant of the stars could pass through the transparent crystal till it reached the earth. The moon was supposed to be in the first sphere, the sun in the fourth, and the fixed stars in the eighth or highest sphere. The cut is intended to illustrate all these particulars.
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