Does some one have a telescope and are near one of the oceans?  I want to see this experiment.  At night go to a cliff overlooking an ocean and try to find things, like mountains or buildings on the other side.  It should work because when it is dark there is less atmospheric interference.  I briefly tried to see if this was done already, but came up with nothing.  I'll keep looking over the internet, and let you know what I find.

Commenting on the bold.  Where on earth can you find a hallway that you can not see the end of?  How long is this hallway?

Depends on the size of the target object.  FEs have made a lot of video on small scale showing, say, a quarter disappearing from bottom up starting within a few feet on a perfectly flat surface like a table if you put the camera aperture low to the surface.  And that's without the additional complication of atmosphere.  Between perspective and atmosphere, there's no way you could see forever.  Even the anti-FE Dr. Sungenis conceded this point.  Now, even without atmosphere it's absurd that scientists claim they can see things from billions of light years away.  I don't care how big the thing is.  They rely on people not knowing how far those absurdly large numbers mean something is.  Separate question though.

You can cut through some of this by using infrared, and JTolan has some amazing infrared photography from altitude where he can see mountains from many thousands of miles away ... though even there they look pretty small.  Depending on the relative distances, something as small as a 10-foot-tall wall could block something that's 10,000 feet tall.  In fact, 2 inches of my thumb can block a skyscraper ... all depending on the perspective math.

So, from my own perspective, and journey, if you will (though the Conciliars have polluted that term by overuse), I was a strong believer in the globe.  In fact, it had taken me a fair bit of time even to open up to geocentrism.

At one point, a few FEs showed up here, some of whom belong to a group "Flat Earth Trads".  So, I did think it was nuts (gut reaction), yet even then I had enough respect for them where I never mocked them, ridiculed them, used insults, smears, or emojis.  In fact, having always been inclined to keep an open mind about almost everything, I was determined to have a look.  Since I didn't think it was going to be particularly credible, I didn't spend a ton of time on it at first.  Matthew had banished them to an "FE" sub-forum here, since Matthew too was against the whole idea, nor did you see the latest threads on that summary panel, so it was easy to forget about them, out of sight, out of mind.  Every once in a while, though, I'd remember and so I'd hop in there to see what they were posting.  I was determined to at least give them a fair shake.  I figured that I'd at least have a look at what they had to say, not expecting anything of much substance and thinking that it wouldn't consume a great deal of my time, since I'd have a look and then run along.

Well, as I read their argument, I found that they actually made some solid points, and so i kept having to look deeper.  I was wrong that there was "nothing to it".  In fact, if you look at Dr. Sungenis' initial interview about his book on FE that had not yet come out but he was talking about ahead of time, he said exactly the same thing.  He had been asked by Kolbe Center to refute FE, and he figured it would be a two-page article, since they've have nothing of substance ... but then it ended up as a book of several hundred pages ... because, as he admitted, they did have some solid arguments that needed to be addressed, and it wasn't just craziness.  It was in fact during that interview that he also made the comment dismissing the argument that you can't see forever on the earth.  I'll come back to his book later, but I did buy it, even though by that time I had become a convinced FE proponent ... respecting the intellectual honesty he appeared to show there in that one interview, and also based on his prior work for geocentrism, e.g. The Principle movie.  Well, the book was exactly the opposite ... and so I was disappointed, but I won't side track here.  I'm always open to being challenged, and so I figured that if my belief in FE could stand up against what I expected to be the strongest and most rational treatment of the subject out there from Dr. Sungenis, then it would only strengthen my convictions, or else I was open to being wrong and corrected on the matter.  Sadly, it was filled with the same tired old nonsense, personal attacks, etc. ... something that was completely uncharacteristic for him.

In any case, so as not to get ahead of myself, I started looking at those posts by FE Trads, and so kept looking further and further.  After about 6 months or so, I was almost incredulous to find myself "leaning Flat Earth", as I termed it.  So I did the introspection there.  WHY did this bother me so much?  I realized that it was due to the psychological conditioning where this cosmology, this entire view of the created universe, had been ingrained in me since my earliest childhood, with my first school science project being that solar system model made of styrofoam balls ... and every teacher had a globe on their desk (just an accident?).  Nor did I relish the thought of becoming an FE and being on the receiving end of extreme ridicule (contrary to popular belief, very few of us like being treated this way) ... ESPECIALLY if I was wrong.  I continued to hold out the possibility that I was wrong, and it wasn't until I was over 99% convinced that the earth is flat that I came out in support of it, since even a 5% uncertainty would have caused sufficient trepidation in me where I'd never hear the end of it for the rest of my life ... if I were wrong about it.

See, a lot of people, if they have an inclination to believe something, might take the leap if they're over 50% sure, or maybe 75% sure, etc.  It's a leap they WANT to take, so they'll bridge the gap in that degree of uncertainty with their wanting to believe that conclusion.  For FEs, it's completely the OPPOSITE, where if there's a 5% gap of uncertainty, the leap is still "too risky".  As a metaphor, pretend that you're jumping from one elevated object to another.  If I'm jumping from one platform to another ... where both platforms are 2 feet off the ground, I'm willing to try it even if I think there's a good chance I won't make it, since the consequences of not making it are next-to-nothing.  But, if the two platforms are 1,000 feet above the ground and the consequences of not making it are fatal, then you're going to be reluctant to take that leap until you're absolutely sure you're gonig to make it ... maybe from no more than 1-2 feet away at the most.  That's the metaphor for FE.  Since the consequences of being wrong (being ridiculed, discredited, etc.) are so severe, it took me 2 years before I felt that, yeah, I'm about 99% certain that the earth is Flat.  Now, once I believe somthing to be the truth, I accept the ridicule ... if in fact I believe that the subject is worth promoting.  If it was something stupid like whether Elvis was still alive ... I wouldn't accept ridicule for that, since it's relatively meaningless.  But FE is incredibly important, since so many millions of souls have lost faith or at least natural belief in God on account of the lies of atheistic modern science.  If the earth is flat and covered by a firmament ... atheism dies a quick death, and many souls have a huge obstacle to faith removed.  Many prominent FEs were atheists or agnostics before being convinced of FE, and then they came to believe in God.  Even though I know of few who became Catholics, it's definitely a step in that direction (were the Church not at the same time crippled by Vatican II and its aftermath).

Now, not all FE proponents were open to FE.  Some in fact set out deliberately to debunk it, thinking it was a psy-op ... since some of them were advocates of the moon landing having been a hoax, and so they figured FE was a way to discred that.  Well, some of them started to dig in and became convinced, despite starting out hostile to it and with the explicit intent of debunking.  That actually lends additional credibility to the cause.  I guess the one thing they had going for them is that they DID NOT BELIEVE or TRUST NASA, and at the end they found that the only actual "evidence" for FE comes from NASA, so it you can't trust them as far as you can throw them (and it's obvious that they're a pack of liars ... to say nothing of their occult and Masonic foundations) ... where does that leave the state of evidence for the globe?  There's almost nothing left if you take NASA out of the equation.

So, about every issue except what has been taugth by the Church, I keep an open mind.  I always test my own conclusions by pretending that I'm debating the subject as a proponent for the other side, and laying out the best arguments I can in favor of that position.  That's very similar to the scholastic method, where you start with the strongest objections, and it's also like that old saying attributed to Sherlock Holmes where if you eliminate the impossible, what remains must be the truth.  So if there are, say, 5 viable opinions, and you decisively eliminate and falsify 4 of them, that makes that last one standing the true one ... unless of course there's one out there that hasn't been thought of yet.  I've done this with evolution, with old earth, with big bang cosmology, and now with globe vs. flat earth.  This exercise isn't difficult for me, since I used to debate in High School and University, participating in various national collegiate debate tournaments, and very often you were required to be prepared to argue EITHER side of the debate topic for a particular season.  You would randomly have to either be for or against the debate resolution / assertion.  It's incredibly "sophistic" ... if done to win and to persuade people of something you don't even believe yourself (since you can't believe both sides), but there's also a good use for this approach, when you're tyring to seek truth (rather than convince someone else).  In any case, I pretend I'm a glober debating flat earthers (here on CI or elsewhere).  I find that I can't come up with anything convincing regardless of how hard I try ... and I have tried.  NASA.  Sorry, but I don't believe NASA is a valid argument, since they're a pack of liars, have an agenda, and are completely imbued with Masonry and the occult.  Dr. Sungenis says that it's a fallacy to conclude they're lying about everything just because they lied about one thing (Sungenis admitted a couple of their lies).  Well, he's actually committing a strawman fallacy.  We don't say they're lying about everything.  But if they lie about anything, they can't be trusted as telling the truth about everything, so you can't just take their word for it, but must evaluate each point on its own merits.  That's actually a legal principle of falsus in uno, falsus in omnibus "false in one thing, false in all", which doesn't mean it's certain in an absolute sense, just that you have to assume they MIGHT BE and therfore nothing they say can be used as evidence in the trial.  For the "see too far" argument, I try throwing the word "refraction" out there like many of them do, but I don't believe it.  Why?  Because I can't convince MYSELF that refraction can explain it, especially from hundreds of miles away sometimes, and with the two-way laser experiments.  It's just a word you throw out there out of desperation as a last-resort deus ex machina to "save the day" for the globe, if you're already pre-convinced.  At best, all I can come up with are certain "Well, with FE, how about ...", where FE don't have a solid answer with proof or evidence, but that doesn't disprove FE, just because it currently doesn't have an answer for it.  Finding some of these questions does not actually positively prove the globe ... except if you're operating under confirmation bias where you take anything as proof.  Now, even IF one could disprove FE, that still doesn't actively PROVE the globe ... since that would rely on the false dichotomy fallacy.  Perhaps the answer is something else, or the answer involves a modification of some pre-existing theory, etc.  So, for instance, maybe the answer is that the earth is a globe but it's much larger than we're told.  I can't refute that ... but then I haven't seen any evidence for this either (not that many people adhere to this).  Or, the answer may be some new theory about how ether could bend light exactly around the countours of the globe.  But I haven't seen that proposed or worked out.  Refraction is utter absurdity, however, so you have to do better than that.  But that's the scientific method, which the globe-proponents, while pretending to appeal to "science", actually ignore the principles of.  What they really mean is an appeal to authority fallacy, an appeal to the mainstream scientific consensus, but not to the scientific method per se, which they merely assume to have already proven globularity.