34 Q. Are there, any other Planets belonging to our System besides the seven already named? A. Other Bodies have been discovered, supposed to be primary Planets, a particular Description of which must be left for future Observations. Some Astronomers reckon also a greater Number of secondary Planets. 35 Q. Are the Planets well accommodated for Inhabitants? A. It is the Opinion of Philosophers, that the Almighty, who never created any Thing in vain, formed these as well as our Earth to be the Habitations of intelligent Beings. ELEMENTS OF USEFUL KNOWLEDGE. PART VI. COMET S. 1Q. WHAT are the Comets? A. A Kind of Planets belonging to our System, but the Periods of whose Revolutions round the Sun are so great that the Nature of them is still unknown. 2 Q. What are those numerous Stars which we see in a clear Evening? A. They are supposed to be Suns, enlightening more distant Worlds; and are called Fixed Stars, because they always keep the same Distances from each other. F 3 Q. Do not the Stars all appear to move like the Sun from East to West? A. This apparent Movement of the Stars, like that of the Sun, is caused by the diúrnal Revolution of the Earth, which is continually carrying us with an insensible Motion* from West to East. 4 Q. How do you know a Planet from a fixed Star? A. The Stars always twinkle; but the Planets shine with a steady Light like the Moon. 5 Q. What is the Cause of this twinkling? A. It is occasioned by small Particles or Vapours, floating in the Air. 6 Q. How many fixed Stars are there? A. The better the Glasses made use of, the greater Numbers have been discover This may be explained by the familiar Circumstance of sailing in a Boat down a River, or travelling in a Carriage along a smooth Road, which gives the Appearance of a retrograde Motion to the surrounding Objects. ed; so that according to the Language of Men, they are innumerable. 7 Q. Is it not possible then to see the whole of the fixed Stars with the Assistance of good Glasses? A. Utterly impossible, as millions of them never have, nor ever can be discovered, by Reason of their remote Dis tance. 8 Q. What do you call that white Appearance, which describes a Path in the Heavens, and is seen in a Star-light Evening? A. It is called the Galaxy, or milky Way; and is supposed to proceed from the Light of a great Number of small Stars, whose vast Distances prevent their being clearly seen. 9 Q. How are the Stars distinguished? A. They are classed into Stars of the first, second, third, fourth, fifth, and sixth Magnitudes: those of the sixth Magnitude being the smallest that can be seen with the naked Eye. They are also divided into Signs or Constellations, according to their Situations in the Heavens. 10 Q. How many Constellations are there? A. Thirty-six in the northern Part of the Heavens, or northern Hemisphere; thirty-two in the southern Hemisphere; and twelve in the Zodiac. 11 Q. What is the Zodiac? A. A broad Circle or Belt, extending round the Heavens, between the northern and southern Hemispheres. 12 Q. Name the twelve Signs of the Zodiac. A. Aries the Ram,/ Leo the Lion, Taurus the Bull, Virgo the Virgin, Gemini the Twins, Libra the Balance, |