10) Ship captains in navigating great distances at sea never need to factor the supposed curvature of the Earth into their calculations. Both Plane Sailing and Great Circle Sailing, the most popular navigation methods, use plane, not spherical trigonometry, making all mathematical calculations on the assumption that the Earth is perfectly flat. If the Earth were in fact a sphere, such an errant assumption would lead to constant glaring inaccuracies. Plane Sailing has worked perfectly fine in both theory and practice for thousands of years, however, and plane trigonometry has time and again proven more accurate than spherical trigonometry in determining distances across the oceans. If the Earth were truly a globe, then every line of latitude south of the equator would have to measure a gradually smaller and smaller circumference the farther South travelled. If, however, the Earth is an extended plane, then every line of latitude south of the equator should measure a gradually larger and larger circumference the farther South travelled. The fact that many captains navigating south of the equator assuming the globular theory have found themselves drastically out of reckoning, more so the farther South travelled, testifies to the fact that the Earth is not a ball.

79.) The remark is common enough that we can see the circle of the Earth if we cross the ocean, and that this proves it to be round. Now, if we tie a donkey to a stake on a level common, and he eats the grass all around him, it is only a circular disc that he has to do with, not a spherical mass. Since, then, circular discs may be seen anywhere – as well from a balloon in the air as from the deck of a ship, or from the standpoint of the donkey, it is a proof that the surface of the Earth is a plane surface, and, therefore, a proof that the Earth is not a globe.

3) The natural physics of water is to find and maintain its level. If Earth were a giant spinning sphere tilting and hurling through space then truly flat, consistently level surfaces would not exist here. There would be a massive bulge of water in the oceans because of the curvature of the earth. If earth was curved and spinning the oceans of water would be flowing down to level and covering land. Some rivers would be impossibly flowing uphill. There would massive water chaos and flooding! What we would see and experience would be vastly different! But since Earth is in fact an extended flat plane, this fundamental physical property of fluids finding and remaining level is consistent with experience and common sense. The water remains flat because the earth is flat!
147) The ball-Earth model claims the Sun is precisely 400 times larger than the Moon and 400 times further away from Earth making them “falsely” appear exactly the same size. Once again, the ball model asks us to accept as coincidence something that cannot be explained other than by natural design. The Sun and the Moon occupy the same amount of space in the sky and have been measured with sextants to be of equal size and equal distance, so claiming otherwise is against our eyes, experience, experiments and common sense.
20.) The common sense of man tells him – if nothing else told him – that there is an "up" and a "down" in -nature, even as regards the heavens and the earth; but the theory of modern astronomers necessitates the conclusion that there is not: therefore, 'the theory of the astronomers is opposed to common sense – yes, and to inspiration – and this is a common sense proof that the Earth is not a globe.
170) People even claim to see satellites with their naked eyes, but this is ridiculous considering they are smaller than a bus and allegedly 100+ miles away; It is impossible to see anything so small that far away. Even using telescopes, no one claims to discern the shape of satellites but rather describes seeing passing moving lights, which could easily be any number of things from airplanes to drones to shooting stars or other unidentified flying objects.
71) It is often possible to see the Chicago skyline from sea-level 60 miles away across Lake Michigan. In 2015 after photographer Joshua Nowicki photographed this phenomenon several news channels quickly claimed his picture to be a “superior mirage,” an atmospheric anomaly caused by temperature inversion. While these certainly do occur, the skyline in question was facing right-side up and clearly seen unlike a hazy illusory mirage, and on a ball-Earth 25,000 miles in circumference should be 2,400 feet below the horizon.
The first photograph (Figure 4) is of a cargo ship bearing the name of the company on its hull. The company is the NYK line, a major Japanese shipping company. Notice that the bottoms of the letters are not visible. The letters on the hulls of cargo ships do not extend to the water line, even when fully loaded, so clearly the bottom of the hull is not visible. This is consistent with what we would expect on a spherical earth, but not on a flat earth. Notice the white bridge castle to the left. The shipping containers are multicolored, and they are stacked at least seven high above the hull directly in front of the bridge castle. Below the visible tiers of the multi-colored containers there is a level of what appears to be gray containers. It is not clear why the containers in this layer are the same color. Finally, notice that the image is a bit blurry. This is because of turbulence in the air between the ship and shore. With increasing distance, the turbulence will get worse, and the images will get blurrier.
Another point concerning timezones, the sun, and Earth: If the sun was a “spotlight” (very directionally located so that light only shines on a specific location) and the world was flat, we would see the sun even if it didn’t shine on top of us (as you can see in the drawing below). Similarly, you can see the light coming out of a spotlight on a stage in the theater, even though you—the crowd—are sitting in the dark. The only way to create two distinctly separate time zones, where there is complete darkness in one while there’s light in the other, is if the world is spherical.
her impossible to "represent" a curved line by a straight one, and absurd to make the attempt, it follows that a straight line represents a straight line and not a curved one. And, Since it is the surface of the waters of the ocean that is being considered by Mr. Young, it follows that this surface is a straight surface, and we are indebted to Mr. Young, a professor of navigation, for a proof that the Earth is not a globe.

 179) If the Earth were constantly spinning Eastwards 1000mph then airplane flight durations going Eastwards vs. Westwards should be significantly different. If the average commercial airliner travels 500mph, it follows that Westbound equatorial flights should reach their destination at approximately thrice the speed as their Eastbound return flights. In reality, however, the differences in East/Westbound flight durations usually amount to a matter of minutes, and nothing near what would occur on a 1000mph spinning ball Earth.
53) At places of comparable latitude North and South, the Sun behaves very differently than it would on a spinning ball Earth but precisely how it should on a flat Earth. For example, the longest summer days North of the equator are much longer than those South of the equator, and the shortest winter days North of the equator are much shorter than the shortest South of the equator. This is inexplicable on a uniformly spinning, wobbling ball Earth but fits exactly on the flat model with the Sun traveling circles over and around the Earth from Tropic to Tropic.

That the mariners' compass points north and south at the same time is a fact as indisputable as that two and two makes four; but that this would be impossible if the thing, were placed on a globe with "north" and "south' at the centre of opposite hemispheres is a fact that does not figure in the school-books, though very easily seen: and it requires no lengthy train of reasoning to bring out of it a pointed proof that the Earth is not a globe.
113) The idea that people are standing, ships are sailing and planes are flying upside down on certain parts of Earth while others tilted at 90 degrees and all other impossible angles is complete absurdity. The idea that a man digging a hole straight down could eventually reach sky on the other side is ludicrous. Common sense tells every free-thinking person correctly that there truly is an “up” and “down” in nature, unlike the “everything is relative” rhetoric of the Newtonian/Einsteinian paradigm.
The lights which are exhibited in lighthouses are seen by navigators at distances at which, according to the scale of the supposed "curvature" given by astronomers, they ought to be many hundreds of feet, in some cases, down below the line of sight! For instance: the light at Cape Hatteras is seen at such a distance (40 miles) that, according. to theory, it ought to be nine-hundred feet higher above the level of the sea than it absolutely is, in order to be visible! This is a conclusive proof that there is no "curvature," on the surface of the sea - "the level of the sea,"- ridiculous though it is to be under the necessity of proving it at all: but it is, nevertheless, a conclusive proof that the Earth is not a globe.
90.) "Is water level, or is it not?" was a question once asked of an astronomer. "Practically, yes; theoretically, no," was the reply. Now, when theory does not harmonize with practice, the best thing to do is to drop the theory. (It is getting too late, now to say "So much the worse for the factsI") To drop the theory which supposes a curved surface to standing water is to acknowledge the facts which form the basis of Zetetic philosophy. And since this will have to be done sooner or later, – it is a proof that the Earth is not a globe.
The best possessions of man are his senses; and, when he uses them all, he will not be deceived in his survey of nature. It is only when some one faculty or other is neglected or abused that he is deluded. Every man in full command of his senses knows that a level surface is a flat or horizontal one; but astronomers tell us that the true level is the curved surface of a globe! They know that man requires a level surface on which to live, so they give him one in name which is not one in fact! Since this is the best that astronomers, with their theoretical science, can do for their fellow creatures - deceive them - it is clear that things are not as they say they are; and, in short, it is a proof that Earth is not a globe.

The Flat Earth Society is a group actively promoting the Flat Earth Movement worldwide. Descending from Samuel Shenton's International Flat Earth Research Society, and the Universal Zetetic Society before it, we continue the age-old tradition of questioning the Round Earth doctrine and challenging authorities. Acknowledging the link between various unconventional beliefs, the Society also occasionally engages in other unconventional debates, striving to provide a voice for all free thinkers and Zeteticists.
20.) The common sense of man tells him – if nothing else told him – that there is an "up" and a "down" in -nature, even as regards the heavens and the earth; but the theory of modern astronomers necessitates the conclusion that there is not: therefore, 'the theory of the astronomers is opposed to common sense – yes, and to inspiration – and this is a common sense proof that the Earth is not a globe.