Occasionally as I've surfed around on Steemit, I've found posts by people who claim to believe that the Earth is not a globe. I've been very clear on my own beliefs on the matter - for example, I discuss [in this post](https://steemit.com/science/@biophil/why-do-i-believe-the-earth-is-a-globe) a few tidbits that help me believe in the rotundity of our planet.

First, I want to make clear: I have no doubt that the Earth is a globe. There isn't a single part of me that says "well, maybe there really is a grand conspiracy, involving many millions of people, to convince me that the shape of the Earth is one thing and not another." I just don't buy it.

But ever since I discovered that some people actually doubt the Earth's roundness, I've found that gathering direct evidence for a globe Earth is a delightful personal hobby, because it heightens my awareness of the world around me. Today I'd like to share a bit of simple evidence that I collected recently.

One of the most difficult problems for a flat-earther is to explain why ships on the horizon disappear hull-first. I suppose their best attempt to explain this damning phenomenon comes from Samuel Rowbotham, the 18th-century charlatan and fear profiteer who [explains it via something he calls the "law of perspective."](http://www.sacred-texts.com/earth/za/za32.htm) He uses many scientific-looking drawings and technical-sounding language to obfuscate his fallacies, and his explanation might just be believable to someone who either does *not* live by the sea or does *not* have a telescope. 

As it happens, [I live by the sea](https://steemit.com/marketplace/@biophil/want-to-buy-your-kayak-surfboard-paddleboard), and I *do* have a telescope (well, not quite - it's a high-powered pair of binoculars. Same-ish thing).

Without further ado, I'll give you the photos I took yesterday. I snapped these with my smartphone held up to the eyepiece of the binoculars, so the quality isn't wonderful. 

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![IMG_20170115_15403615053687.jpg](http://www.steemimg.com/images/2017/01/16/IMG_20170115_15403615053687.jpg)</center>

The subject of this first photo is [Platform Holly](https://en.wikipedia.org/wiki/Ellwood_Oil_Field), a major source of oil production just off the coast of Goleta, California. The platform is about 2 miles off shore. In this article, I'm not going to try to *measure* the curvature of the Earth; I don't know enough about correcting for refraction error to do this properly. I'm just going to look for *qualitative* evidence of curvature.

I took that first photo from the cliffs overlooking the Pacific Ocean, at an elevation of 20-30 feet above the water. Look carefully - you can see the horizon through the legs of the platform. **If the Earth is flat, then no matter what elevation you're looking from, you'll always be able to see the horizon through the legs of the platform.** That is, my second picture would not be possible:

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![IMG_20170115_151747173f4ad6.jpg](http://www.steemimg.com/images/2017/01/16/IMG_20170115_151747173f4ad6.jpg)</center>

I took this photo standing on the beach below the cliffs at an elevation of about 5 feet. See? **The platform appears to be standing directly on the horizon.** Remember, if the Earth is flat, you'll always be able to see through the legs to the horizon. You may not be able to see much horizon, but you'll always see some. Here, you can see none.

For my next pair of photos, I'm looking up the coast at a point of land that protrudes into the ocean. Again, around 2 miles away. This first one is taken from the clifftops:

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![IMG_20170115_155036666_HDRcf2da.jpg](http://www.steemimg.com/images/2017/01/16/IMG_20170115_155036666_HDRcf2da.jpg)</center>

Notice there where a tiny thread of land sticks out into the ocean? You can see a dark horizontal thread below a light horizontal thread; the dark thread is a rock jetty protruding into the water and the light thread is the water that we can see behind it. If the Earth is flat, then as I descend to the beach, those threads would simply become thinner. Instead, this is what happens:

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![IMG_20170115_153441323_HDRa586f.jpg](http://www.steemimg.com/images/2017/01/16/IMG_20170115_153441323_HDRa586f.jpg)</center>

**The threads disappear completely, and the protruding cliffs appear to meet the water at the same level as the distant land in the background.** A flat Earth should still show separation between the foreground cliffs and the background cliffs. What you're looking at in this photo is this: **the foreground cliffs are standing almost directly on the horizon, so any water behind them is behind the curvature of the Earth.**

For my last set of photos, I'll show what you've all been waiting for: something receding past the horizon. I took the following photo from the top of the cliffs; you can see two very distant oil platforms (not the same as the one in the first two photos). 

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![IMG_20170115_155004027_HDRccea8.jpg](http://www.steemimg.com/images/2017/01/16/IMG_20170115_155004027_HDRccea8.jpg)</center>

Look at the one on the right: **You can just see the sky through its legs.** Just barely, but it's there. This platform is sitting directly on the horizon, or perhaps just past it. Now look at this photo of the *right* platform that I took from the beach at the bottom of the cliffs:

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![IMG_20170115_15220505350302.jpg](http://www.steemimg.com/images/2017/01/16/IMG_20170115_15220505350302.jpg)</center>

It has very clearly fallen behind the horizon. On a flat Earth, this would certainly not be possible. I must be very clear on this point: **I have not changed my distance to the subject, I only changed my elevation.** Rowbotham's "law of perspective" offers no help to the flat-earther here. If the Earth were flat and I could see the sky through its legs from the top of the cliffs, then I *absolutely* must be able to see the sky through its legs from the bottom of the cliffs. Instead, I can't see its legs at all.

Here is a photo of the left-most platform taken from the beach:

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![IMG_20170115_152134900_HDR5b80f.jpg](http://www.steemimg.com/images/2017/01/16/IMG_20170115_152134900_HDR5b80f.jpg)</center>

Again, it's clearly disappearing beyond the horizon.

A few parting thoughts before I wrap this up: In this article I've looked for qualitative evidence of the Earth's curvature. I don't have precise-enough instruments to gather quantitative evidence, though I'd love to acquire some. If you're a flat-Earther and you've made it this far, thank you! I hope this has been enlightening to you and will provide much food for thought. I encourage you to think critically about the flat-Earth conjecture; never forget that **science is about disproving false things more than it is about proving true things.** That is, if you really want to believe in a flat Earth, it is your responsibility as a rational and skeptical person to *try your damnedest* to disprove its flatness, however counterintuitive that may seem. In this article, my evidence is valuable as evidence *against* a flat-Earth conjecture; it is far less valuable as evidence *for* a globe-Earth conjecture.