Just thought I'd pop back in here after a long hiatus to see if I can get an answer to a question that was never adequately addressed when I was on here before. Perhaps because it really needs a thread of its own: The little island of Molokini, about 2 3/4 miles from the nearest point of land on Maui, HI.
Wikipedia says that:
Molokini is a crescent-shaped, partially submerged volcanic crater which forms a small, uninhabited islet located in ʻAlalākeiki Channel between the islands of Maui and Kahoʻolawe, within Maui County in Hawaiʻi. It is the remains of one of the seven Pleistocene epoch volcanoes that formed the prehistoric Maui Nui island, during the Quaternary Period of the Cenozoic Era.
At present, Molokini consists of half of the rim of the ancient volcanic crater, in a semicircle, forming a partially-enclosed bay which is a popular snorkeling and scuba diving destination. (Scuba diving is mostly, though not always, on the back wall outside the bay, and snorkeling is mostly near the inside wall.)
Viewed from the north, you see into the crater/bay, and the rim or wall forms a flattened letter M: At its eastern side it rises from the water running north/south, then turns to run east/west and rises to a peak; it then dips down to a low spot at the back of the little bay and then rises to another peak, from which it descends again until at the western side the wall turns north-south and drops back into the sea.
Sometimes I describe it as a bactrian camel, though the "humps" of Molokini are not nearly so pronounced as those of the camel. The point here is that there are two high spots on the wall, with a lower portion between them.
From anywhere in Ma'alaea Bay you see Molokini as a single island with two high points.
That's the background for my question.
Now, we're always told that the ancients knew the Earth was curved because when a ship appears at the horizon, its sails are visible first and the hull later. But my problem is that my eyesight is not good enough to see a sailboat at the horizon at all. But Molokini is enormously bigger than a sailboat.
If, rather than starting in Ma'alaea Bay, you set out from Olowalu, which is several miles farther north, you cannot see Molokini at all. If you then travel south, towards Molokini, you will begin to discern what appear to be two small islands where you know Molokini to be. As you continue south, those islands appear to get bigger and bigger, until finally you can see that it is just one island, and what you were seeing were the two peaks of the crater wall just poking above the horizon line, while the bulk of the crater wall remained below the horizon.
Just as with the sailboat, but clearly visible without the need for exceptionally-good eyesight, the top of the island can be seen from farther away than the base of the island. This is exactly as would be expected on a curved surface: The top of a tall object is visible farther away than is the base.
If the Earth were flat one would expect the entire island to be visible in its entirety once one was close enough to see it. But that's not what happens. Instead, the top is visible first.
I have yet to see an explanation of this from the flat-earth perspective. And that is my question. Thank you.