![zetetic astronomy amazon zetetic astronomy amazon](https://m.media-amazon.com/images/I/31WIbhuzIXL._AC_SY1000_.jpg)
It would of necessity appear as shown in fig. Whereas, if the earth is spherical, and therefore the surface of all water convex, such an appearance could not exist. Whatever test has been employed, the line, where the sea and the land appear to join, is always found to be perfectly horizontal, as shown in the following diagram fig.
![zetetic astronomy amazon zetetic astronomy amazon](https://m.media-amazon.com/images/I/31QE7WIXgmL._AC_SY350_.jpg)
whole length of the Isle of Man, on a clear day and with a good telescope, is distinctly visible, and presents the same horizontal base line as that observed in the Isle of Wight.įrom the high land near Douglas harbour, Isle of Man, the whole length of the coast of North Wales is often plainly visible to the naked eye-a distance extending from the point of Ayr, at the mouth of the River Dee, towards Holyhead, not 18, will prove the same condition to exist viz., that the margin of the Isle of Wight is, for twenty-two miles, a perfectly straight line and instead of curvating downwards 80 feet each way from the centre, as it certainly would if convexity existed, it is absolutely horizontal.įrom the lighthouse on Bidstone Hill, near Liverpool, the. As a proof that such would be the appearance, the same instrument directed upon any object having an upper outline curved in the smallest degree, will detect and plainly show the curvature in relation to the cross-hair a b or the levelled board employed in experiment 7, fig. If the earth is globular, the two ends east and west of the Isle of Wight would be 80 feet below the centre, and would appear in the field of view of the theodolite as represented in fig.