70 



SCENERY OP THE HEAVENS. 



THE EARTH. We now come to the abode of Man the cradle, the home, and the grave 

 of our race for a period of six thousand years the third planetary body in point of distance 

 from the central sun, and the first in the system of which we have certain knowledge of 

 its being dignified with the presence of an attendant orb. The introduction of our globe 

 to a place among celestial objects involves an apparent contradiction ; yet such is its real 

 character in the constitution of the universe, and such is its obvious aspect as viewed 

 away from its surface. To rustic ignorance it will seem a statement palpably absurd, 

 that any affinity exists between the earth and the stars in the firmament. They are 

 mere points of light in the sky, and have no perceptible dimensions, whereas our world 

 appears of immeasurable extent, and exhibits no luminosity like theirs to the eye of 

 sense. It seems, too, a perfectly inert mass. There is no movement discernible inde- 

 pendent of that of the rivers flowing in their channels, the seas tossing in their bed, and 

 the forests bending to the gale, while the celestial bodies appear in constant procession 

 from place to place in the concave of the heavens. There is nothing, however, more 

 susceptible of demonstration^ than that the obvious state of our globe is not its actual 

 condition that the apparently quiescent habitation of mankind is an unceasing traveller 

 in space that its opaque mass exhibits the same luminous aspect to the nearer planets 

 which they present to us and that in structure and economy the earth is in fraternal 

 relationship to the celestial host, and may be denominated, with perfect propriety, a star. 



Physical science, in the three departments of astronomy, geography, and geology, deals 

 with the mass of our globe. The former is chiefly concerned with its figure and magni- 

 tude, its atmosphere and motions. 



To the eye the earth appears an immense plain stretching out in all directions to an 

 indefinite extent. This was the current opinion of mankind respecting its form in early 

 times. But a few simple facts prove the suggestion of the senses here to be erroneous. 

 The limit of vision to the traveller upon an extensive level, or to the mariner at sea, is a 

 well-defined circle of which the observer is the centre ; and it may be geometrically 



v 



proved, that this circular horizon is a certain indication of the circular figure of the body 

 to which it relates. In any direction in which a ship leaves shore, or approaches the 

 coast, the vessel is observed as if gradually sinking in the ocean, or rising from it 



