People have believed that the Earth is flat since the beginning of humanity, but the modern Flat Earth hypothesis stemmed from an experiment called the Bedford Level Experiment, conducted in the mid-1800s by a man named Samuel Rowbotham.[1] Rowbowtham, who wrote a book named Earth Not a Globe, started the modern movement by debating scientists publicly and accumulating followers. In the experiment, Rowbowtham attempted to measure the curvature of the earth by observing the curvatures at a local river. He took his results as disproving the theory of a round earth, but future scientists have said that the results he obtained could be accounted for by the parallax effect.[2]
155) Some people claim to have seen the curvature of the Earth out their airplane windows. The glass used in all commercial airplanes, however, is curved to remain flush with the fuselage. This creates a slight effect mixed with confirmation bias people mistake for being the alleged curvature of the Earth. In actuality, the fact that you can see the horizon at eye-level at 35,000 feet out both port/starboard windows proves the Earth is flat. If the Earth were a ball, no matter how big, the horizon would stay exactly where it was and you would have to look DOWN further and further to see the horizon at all. Looking straight out the window at 35,000 feet you should see nothing but "outer-space" from the port and starboard windows, as the Earth/horizon are supposed to be BELOW you. If they are visible at eye level outside both side windows, it’s because the Earth is flat!

On January 25th, 2016 Atlanta rapper B.o.B., who has self-identified as a member of the Flat Earth Society, tweeted a photograph of himself against a skyline, then tweeted a screenshot from Flat Earth Movement literature that proclaimed that Polaris (the North Star) can be seen 20° south of the Equator. Neil DeGrasse Tyson answered the rapper's question, writing "Polaris is gone by 1.5 deg S. Latitude. You’ve never been south of Earth’s Equator, or if so, you've never looked up."
If the circular motion of the Sun is a wider circle in December and Shorter in June and it still completes a circle in 24 hours, that Must mean the Speed of the Sun's travel changes accordingly right? Now a fixed spinning record will have one speed but depending on where on the record you are your linear motion will be different. Does this mean then, to achieve the change in speed for a FE Sun, it would need to be affixed to something unseen that is rotating?
69.) Mr. Lockyer says: "The appearances connected with the rising and setting of the Sun and stars may be due either to our earth being at rest and the Sun and stars traveling round it, or the earth itself turning round, while the Sun and stars are at rest." Now, since true science does not allow of any such beggarly alternatives as these, it is plain that modern theoretical astronomy is not true science, and that its leading dogma is a fallacy. We have, then, a plain proof that the Earth is not a globe.
Astronomers tell us that, in consequence of the Earth's "rotundity," the perpendicular walls of buildings are, nowhere, parallel, and that even the walls of houses on opposite sides of a street are not! But, since all observation fails to find any evidence of this want of parallelism which theory demands, the idea must be renounced as being absurd and in opposition to all well-known facts. This is a proof that the Earth is not a globe. 

Astronomers are in the habit of considering two points on the Earth's surface, without, it seems, any limit as to the distance that lies between them, as being on a level, and the intervening section, even though it be an ocean, as a vast "hill"-of water!" The Atlantic ocean, in taking this view of the matter, would form a "hill of water" more than a hundred miles high! The idea is simply monstrous, and could only be entertained by scientists whose whole business is made up of materials of the same description: and it certainly requires no argument to deduce, from such "science" as this, a satisfactory proof that the Earth is not a globe.

It has been shown that an easterly or a westerly motion is necessarily a circular course round the central North, The only north point or centre of motion of the heavenly bodies known to man is that formed by the North Star, which is over the central portion of the outstretched Earth. When, therefore, astronomers tell us of a planet taking a westerly course round the Sun, the thing is as meaningless to them as it is to us, unless they make the Sun the northern centre of the motion, which they cannot do! Since, then, the motion which they tell us the planets have is, on the face of it, absurd; and since, as a matter of fact, the Earth can have no absurd motion at all, it is clear that it cannot be what astronomers say it is - a planet; and, if not a planet, it is a proof that Earth is not a globe.
In the next photograph and succeeding photographs, the ship is farther away, as indicated by the decreasing apparent size of the ship. In Figure 5, an inferior mirage is starting to show up. At the edge of the water, you can see a gray line, which is an inferior mirage of the row of gray containers right above the hull. On the right side of the ship, you can see the inferior mirage of the bow. The hull protrudes forward there, and the small white patch just above is a small portion of the forecastle. Notice that the inferior mirage of the bow is inverted, as one would expect. It is difficult to see here, but the lettering on the hull also is undergoing an inferior mirage too.

19) Tycho Brahe famously argued against the heliocentric theory in his time, positing that if the Earth revolved around the Sun, the change in relative position of the stars after 6 months orbital motion could not fail to be seen. He argued that the stars should seem to separate as we approach and come together as we recede. In actual fact, however, after 190,000,000 miles of supposed orbit around the Sun, not a single inch of parallax can be detected in the stars, proving we have not moved at all.
118) Furthermore, the velocity and path of the Moon are uniform and should therefore exert a uniform influence on the Earth’s tides, when in actuality the Earth’s tides vary greatly and do not follow the Moon. Earth’s lakes, ponds, marshes and other inland bodies of water also inexplicably remain forever outside the Moon’s gravitational grasp! If “gravity” was truly drawing Earth’s oceans up to it, all lakes, ponds and other bodies of standing water should certainly have tides as well.
Considerably more than a million Earths would be required to make up a body like the Sun -the astronomers tell us: and more than 53,000 suns would be wanted to equal the cubic contents of the star Vega. And Vega is a "small star!" And there are countless millions of these stars! And it takes 30,000,000 years for the light of some of those stars to reach us at 12,000,000 miles in a minute! And, says Mr. Proctor, "I think a moderate estimate of the age of the Earth would be 500,000,000 years! "Its weight," says the same individual, "is 6,000,000,000,000,000,000,060 tons!" Now, since no human being is able to comprehend these things, the giving of them to the world is an insult - an outrage. And though they have all risen from the one assumption that Earth is a planet, instead of upholding the assumption, they drag it down by the weight of their own absurdity, and leave it lying in the dust - a proof that Earth is not a globe.

136) Many people think that modern astronomy’s ability to accurately predict lunar and solar eclipses is a result and proof positive of the heliocentric theory of the universe. The fact of the matter however is that eclipses have been accurately predicted by cultures worldwide for thousands of years before the “heliocentric ball-Earth” was even a glimmer in Copernicus’ imagination. Ptolemy in the 1st century A.D. accurately predicted eclipses for six hundred years on the basis of a flat, stationary Earth with equal precision as anyone living today. All the way back in 600 B.C. Thales accurately predicted an eclipse which ended the war between the Medes and Lydians. Eclipses happen regularly with precision in 18 year cycles, so regardless of geocentric or heliocentric, flat or globe Earth cosmologies, eclipses can be accurately calculated independent of such factors.

16.) If the, Earth were a globe, the distance round its surface at, say, 45 "degrees" south latitude, could not possibly be any greater than it is at the same latitude north; but, since it is found by navigators to be twice the distance — to say the least of it — or, double the distance it ought to be according to the globular theory, it is 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!