Does Earth Really Rotate and Review of Earth Shape

Author(s): Abhaysagar
Publisher: Jambudvi Vignyan Research Centre

Page 29

of the whole ship. Why so? Can the camera-lens or telescope lens remove the curvature of the earth ? Thus the attempt to prove that the earth is round by saying "The visible needs no proof" is ridiculous.
Perhaps here the question may arise “If the curvature of the earth does not come between the steamship and the observer, then why can he not see the whole of the steamship? Why can he see the chimney or the mast only?” The simplest reply to this it is the queer result of our limited capacity of vision. (See picture on page 41)
Scientist say about the round shape of the earth that the top-most part of a ship is seen first of all. Then gradually the whole ship unfolds itself down from the top to the bottom. This is shown in the diagram. But this is only an optic illusion, because one can see the top most part first with naked eye but with the help of telescope the whole of the ship can be seen. ILLUSTRATIONS OF OUR LIMITED CAPACITY OF VISION :
To understand the apparent queer results of our limited capacity for vision, it is necessary to know that our eyeball is convex. It makes us see anything when the vision of both the eyes meets at a right angle. And so sometimes the vision is imperfect. As for an illustration, if we stand between two rails of a train, and cast a far off glance (about two furlongs ) the rails will appear meeting each other. This is only an optic illusion resuting from the limted capacity of human vision. In fact, whether broad gauge or metre gauge, the rails are always parallel; otherwise how can trains run so smoothly on them ? This is a matter of universal experience.
In the same way if we cast a glance at a long straight tarroad, we find the two sides of the road meeting on the horizon. But if we walk over a long distance on the same road, we will find the horizon going farther and farther. This is also one more example of an optic illusion. We experience many such illusions in our practical life.
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