Celestial globe

“ The celestial globe topping the goblet is given an artistic setting. It is furnished with horizon, meridian, and hour circles. The several constellations represented on the surface of the sphere are, through gilding, given special prominence, their execution, like other parts of the piece, being of the finest workmanship.
The figure of Atlas supporting the globes exhibits skill in its construction. It stands with one foot slightly advanced, with the right hand extended upward as if to catch the ball should it fall from the head of the figure. ”

“ At the center of the sphere, the inner surface of which, as stated above, represented the starry heavens, was placed a small ball, about 15 cm. in diameter, representing the earth. The great globe, driven by water power, was therefore made to appear to revolve around this central terrestrial globe. A representation of the sun, made of glass, had its own proper motion along the circle of the ecliptic, and a representation of the moon likewise was made to move in its own proper course. ”

“ In his second attempt at globe making, his boyish ingenuity particularly exhibited itself. Finding two large globular stones on the top of a neighbor’s gate-posts, he painted on one of these, with oil colors, a map of the terrestrial globe, and on the other a map of the celestial, from a planisphere of the stars which he had copied on paper from a celestial globe belonging to a neighboring gentleman. “The poles of the painted globes stood toward the poles of the heavens. ”

“ This globe of marble is not so mounted as to permit its revolution, resting as it does upon the shoulders of the mythical Atlas, yet in its representation of the figures of the several constellations, then recognized by astronomers, it differs practically but little from the celestial globes, that is, solid spheres, constructed a millennium and a half later.182 We cannot, however, draw the conclusion from this one example that such globes were generally looked upon as practical instruments for use in astronomical studies, yet there clearly were those who did so regard them. ”

“ Upon the sphere, besides the principal circles of the celestial globe, the Zodiac is placed, of a breadth sufficient to contain the apparent path of the moon, with all the stars over which the moon can pass, also the ecliptic, and the heliocentric orbits of all the planets. The Earth in the planetarium has a moveable horizon, to which a large moveable brass circle within the sphere may be set coincident, representing the plane of the horizon continued to the starry heavens. ”

“ The celestial globe referred to above has represented on 179its surface the several Ptolemaic constellations, exquisitely colored, and the stars have been given names in Greek, Latin, and Arabic. The terrestrial globe map is considerably injured, especially in the polar regions, but the continental and other outlines are all clearly traceable. Three large compass roses, of ornamental pattern, are placed along the Line of Demarcation. The coast outline of Europe is, in the main, well done, as is that of Africa and the New World. ”

“ On the celestial globe the greater and the lesser circles were represented in gilt bronze, and were so graduated for both latitude and longitude, ascension and declination, that it was made easy for an astronomer to pass from one co-ordinate to the other without the aid of trigonometry. On a fine background of ultramarine the several constellations with their respective figures were represented, each of the planets and fixed stars being gilded in order to give it due prominence. ”

“ As a record of the geographical knowledge of the time, this Hondius terrestrial globe map may justly be referred to as one of the most valuable of the period.
Fig. 90. Dedication Appearing on Globe of Jodocus Hondius, 1600.
For astronomical study the celestial globe is none the less valuable and interesting than is the terrestrial for the study of geography. Its descriptive title reads: “Globus coelestis. In quo Stellae fixae omnes quae a N. viro Tycone Brahe sūma industria ac cura observatae sunt accuratissime designantur: nec non ea quae a peritis. ”

“ It is not easy to fix, with anything like a satisfactory measure of certainty, the beginning of globe construction; very naturally it was not until a spherical theory concerning the heavens and the earth had been accepted, and for this we are led back quite to Aristotle and beyond, back indeed to the Pythagoreans if not yet farther. We find allusions to celestial globes in the days of Eudoxus and Archimedes, to terrestrial globes in the days of Crates andxxii Hipparchus. ”

“ Below, and occupying the middle region, revolves the Sun, the chief, prince, and moderator of the other stars, the soul of the world, whose immense globe spreads its light through space. After him come, like two companions, Venus and Mercury. Lastly, the lowest globe is occupied by the moon, which borrows its light from the star of day. Below this last celestial circle, there is nothing but what is mortal and corruptible, except the souls given by a beneficent Divinity to the race of men. ”

“ Carrington, is it possible to establish a celestial globe that is capable of giving a negative action? No, wait, I'll explain. Our present celestial globe is positive; it operates by three-dimensional fluorescence in the sphere, glowing when a positive radiation comes in from a spaceship. ”

“ It is said that one of these instruments was so skilfully constructed that even the untrained by its use, having one constellation pointed out, would be able to locate all others “with the aid of a globe and without the aid of a teacher.”84 In a letter to the monastic teacher Constantius, with whom Gerbert stood in the friendliest relations for many years at Rheims, he refers to the construction of a celestial globe, and in a more detailed manner he makes mention of this when writing to Remigius of Trier. ”

“ On one of these should be represented all the celestial constellations, and the circles should all have their place, that is to say, not as Ptolemy represents the stars as they were located in his time, but according to the investigations of our own times, that is, about twenty degrees further east. The other should be a terrestrial globe constructed according to modern ideas, which he should always follow in his studies. He will use the first globe for a thousand and one things ”

“ Thales’ ideas, probably not a globe maker.—Eudoxus.—The Atlante Farnese.—Archimedes.—Allusion of Lactantius.—Pappus’ allusions.—Armillary spheres.—The astronomer Hipparchus.—Ptolemy.—Globes used for decorative purposes by the Romans.—Roman coins.—The Byzantine Leontius Mechanicus.
THOUGH we find but an occasional reference to terrestrial globes in the literature of classical antiquity, numerous statements appear therein which assure us that celestial globes, solid balls as well as armillary spheres, were constructed in those early centuries, for both practical and ornamental purposes. ”

“ Having now described, and prepared the Planisphere for use, I shall next explain the motions of the Terraqueous Globe on which we live: and first, according to the true, or Copernican System of the Universe, this Globe is a Planet, revolving round the Sun in an orbit somewhat elliptical, and in the space of 365 days, 5 hours, and 49 minutes, being accompanied with the Moon, and hath the Sun at rest in the center of its orb.–Now, conceive at a vast distance, without this system, the sphere of the fixed Stars ”

“ The globe base, very artistically wrought, rests upon four griffin’s feet, between which a small terrestrial globe 10 cm. in diameter has been placed, this having been furnished with its own independent support. The large celestial sphere is furnished with a clocklike mechanism by means of which it is made to revolve in representation of the diurnal motion of the heavens. According to existing records it was purchased in the year 1593 by order of the Elector Christian II, and by him was presented to the Academy of Arts of Dresden. ”

“ A small globe representing the celestial sphere, on which the apparent positions of the stars are indicated. It is usually provided with graduated arcs and a suitable mount for determining the approximate altitude and azimuth of the stars, to serve as a star finder. Star globes are more commonly used by the British than by Americans. ”

“ We have traversed a distance which even on [Pg 135] the wings of light we could only accomplish in many thousands of years, and now stand on the outskirts of our great star cluster, in the same way, and I hope with the same aspirations, as when we paused the last time on the confines of our Solar System. Behind us are myriads of shining orbs, in such countless numbers that human thought cannot even suggest a limit, and yet each of these is a mighty globe like our Sun, the centre of a planetary system, dispensing light and heat under conditions similar to what we are accustomed to here. ”

“ The spectator on the sea between, if he can discard from mental vision the vessel on which he stands, and regard only these two great globes of Heaven and the sea-horizon circling unbroken around him, gains a conception through this spectacle clearer than any other conjunction can give, of those wonderful relations which it is the triumph of astronomy to disclose. All objects are excluded save the Sun, the Moon, and our own Globe between, but these objects are such in themselves that their very simplicity and paucity of number enhances the sense of the sublime. ”

“ And the scene is wrapped in somnolence and rest.
From a solitary star, in the realms of space afar,
Faintly twinkling through the shadows of the night,
See the stellar force increased, till the scintillating east
Seems a galaxy of constellations bright. 127
With its glittering display, see the gorgeous Milky Way,
Which in twain the vaulted universe divides,
As the bridal veil serene of some fair celestial queen,
Who, in jewelled state, o'er astral space presides.
All the heavens seem in tune, and the vacillating moon
Bathes the landscape with her floods of silvery light ”

“ It descends to us from the solar orb. It wings its way through the voids of space, along a course of ninety-five millions of miles, till it arrives at the outskirts of our globe; it passes freely through the surrounding atmosphere, it strikes upon the clouds and is reflected by them; it irradiates the mountains, the vales, the forests, the rivers, the seas, and all the productions of the vegetable kingdom, and adorns them with a countless assemblage of colours. It scatters and disperses its rays from one end of creation to another, diffusing itself throughout every sphere of the universe. ”

“ If the earth were brought down in size to an ordinary large school globe, a piece of rough brown paper covering it might well represent the thickness of this earth-crust, with which the science of geology has to do. And the whole of the globe, this earth of ours, is but one tiny planet in the great Solar System. And the centre of that Solar System, the blazing sun, though equal in size to more than a million earths, is yet himself but one star amid millions of twinkling stars, scattered broadcast through the universe. ”

“ The Sun existing and being the centre of its system, the Earth, all the planets and their satellites, are dependent upon it, and to it their destiny is irrevocably bound.
Is the fixed point that we are seeking, the solid base which we seem to need to insure the stability of the universe, to be found in that colossal and heavy globe, the Sun? ”

“ Myriads of luminous globes, placed at immense distances, are the bases which support the fabric of the universe, and millions of opaque globes, which circulate round them, constitute the moving order of its architecture. By two primitive forces, each of which are in continual action, these masses are revolved and carried through the immensity of space; and their combined efforts produce the zones of the celestial spheres, and in the midst of vacuity establish fixed stations, and regular routes and orbits. ”

“ The fact that the planets shine by the sun's light points at once to the similarity between them and our earth. We are thus led to regard our sun as a central fervid globe associated with a number of much smaller bodies, each of which, being dark itself, is indebted to the sun both for light and for heat.
That was, indeed, a grand step in astronomy which demonstrated the nature of the solar system. The discovery that our [Pg 114] earth must be a globe isolated in space was in itself a mighty exertion of human intellect ”

“ Thus, in the sublime chronology to which we are directing our inquiries, we first find ourselves called upon to consider the globe which we inhabit as a child of the sun, elder than Venus and her younger brother Mercury, but posterior in date of birth to Mars, Jupiter, Saturn, and Uranus; next to regard our whole system as probably of recent formation in comparison with many of the stars of our firmament. We must, however, be on our guard against supposing the earth as a recent globe in our ordinary conceptions of time. ”

“ You will perceive that all points in the upper hemisphere are longer in light than in darkness, because the plane dividing the illuminated and the unilluminated halves of the globe is inclined to the globe's axis in such a way that it lies beyond the upper pole as seen from the direction of the lamp. Consequently, the upper half of the globe above the equator, as it goes round, has more of its surface illuminated than unilluminated, and, as it turns on its axis, any point in that upper half, moving round parallel to the equator, is longer in light than in darkness. ”

“ The Horizon, the Zenith, and the Meridian. First, let us consider what is the ordinary appearance of the sky. When we go out of doors on a clear night we see the heavens in the shape of a great dome arched above us and filled with stars. What we thus see is one half of the spherical shell of the heavens which surrounds us on all sides, the earth being apparently placed at its centre. The other half is concealed from our sight behind, or below, the earth. This spherical shell, of which only one half is visible to us at a time, is called the celestial sphere. ”