2155: Swimming

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"You don't know how high above you the sky goes, but you're not freaking out about that." "Well, NOW I am!"
Title text: "You don't know how high above you the sky goes, but you're not freaking out about that." "Well, NOW I am!"


This comic is about an irrational fear about the depth of water beneath oneself, also known as thalassophobia. Whenever you don't explicitly know how deep the water is, and cannot see the bottom, there is nothing preventing the sea/lake/riverbed from being exceptionally far away. This phenomenon is actually quite common with many bodies of water having a relatively shallow shelf extending a short ways out from land. These typically end with little to no warning, giving rise to the fear that is depicted here.

It is an irrational fear because if one is swimming, the depth of the water underneath is not important to safety as long as one can reliably get back to shore. (This fear may be due to excessively worrying about what happens if one stops swimming, thinking that walking should be safer because almost everyone spends more time walking than swimming, ignoring the fact that the safest thing to do in this case is to keep swimming.) If one is wading, presumably one would feel the bottom drop away. Following the safety saying "Walk out, swim back" would help avoid this situation.

Here, Megan and Cueball are in the ocean, with Cueball treading water and Megan standing on the seabed, with another girl in the water and another Cueball watching from the beach. Megan mentions that she can still touch bottom, thus thinking it is safe. In front of her however the seabed drops off steeply, becoming nearly vertical. Fish and jellyfish are in the water below, while at the bottom of the frame, but not the sea floor, a small ledge holds an octopus and a beach umbrella. The beach umbrella may be from the beach, to give human scale, though it could also be a Lemmings reference.

The title text alludes to the fact that humans live at or near the bottom of a vast sea of air: the atmosphere. Every day, most people never rise far from the floor of the atmosphere. However, this is nowhere near as perilous as descending to the bottom of a sea of water. Indeed, surviving a rise to the top of the atmosphere requires life support measures. Also, unlike in water, humans are far too dense to "swim" (fly) in the atmosphere.


  • Assuming the height of characters is 1.7 m, the depth of the shallows is about 1.1 m, and the ledge is 77 m deep.

Related comics[edit]

  • In 731: Desert Island a similar vision of not knowing what is beneath the surface is depicted.
  • Randall provided the depths of various bodies of water without mentioning any specific fears in 1040: Lakes and Oceans.
  • The title text may be a reference to 1115: Sky, where Megan similarly starts freaking out about the depth of the sky.
  • The what if? article Vanishing Water covers what would happen if all the bodies of water vanished. It refers to the sharp drop-off of the continental shelf, and divides boats into two categories: those over the shelf that crash within a few seconds, and those past the shelf that take up to a minute to reach bottom.


[The single panel comic is around 4 times higher than it is wide (317×1284 pixels). A Cueball is watching from the beach while Megan with another character is standing neck deep in water near an extreme drop off (continental shelf?) and another Cueball is swimming further, and there is a fish behind him. This part of the comic is at the very top, and the characters are drawn much smaller than usual.]
Megan: It's OK, I can still touch bottom here.
[As the tall image is scrolled down, there is a school of three fish, a jellyfish, a single deep-water fish, an octopus, a bottom ledge with a toppled beach umbrella on it, and another drop off. The second drop is mostly cut off by the edge of the panel.]
[Caption below the panel:]
I love swimming, but occasionally I realize I don't know how deep the water under me is and it freaks me out.

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The title text reminds me of https://xkcd.com/1115/ 17:22, 27 May 2019 (UTC)

I never fully enjoyed swimming in lakes & oceans for this same reason. Getting nipped by a snapping turtle, pinched by crawfish & crabs, & nudge-tested by snakes probably pushed my experiences in a negative direction as well. Chlorine & urine content don't make swimming pools nearly unpleasant enough to feel ickier than most open water I've been in. As someone who grew up in a hot climate, I love swimming, but I like to be able to see what's in the water around me. The deeper & murkier the water is, the more uneasy I feel venturing into it. ProphetZarquon (talk) 17:49, 27 May 2019 (UTC)

In most open water, there is no chlorine, but there is definitely some urine and blood and probably also fish sperm. It SHOULD be more diluted, though ... -- Hkmaly (talk) 22:15, 27 May 2019 (UTC)
I find it ridiculous that some people are grossed by the supposedly urine (or, God forbid, sperm) contaminated swimming pools yet fine to drink water coming from open reservoirs containing (highly diluted!) duck poop, fish stuff, slimes and molds etc. Some even have spilled millions of gallons of perfectly fine water after some guy peed in it, even if it was wide open to any flying source of poo ([1]) -- Malgond (talk) 08:27, 28 May 2019 (UTC)
Most people don't rely on swimming pools for their drinking water. (Should I <citation needed> myself?) Neither do they drink directly from reservoirs without there being some filtering and conditioning in the delivery system. These Are Not The Comments You Are Looking For (talk) 00:27, 3 June 2019 (UTC)
haha. I live in Australia. I love swimming at the beach. But my rule is, as much as possible, always swim with someone bigger, slower and further out. The first two are not as easy as they used to be!!Boatster (talk) 13:43, 28 May 2019 (UTC)
also " nudge-tested by snakes" W.T.A.F!!!Boatster (talk) 13:45, 28 May 2019 (UTC)

I am confused. The explanation says there is a person as you scroll down, but I don't see any people below the surface. Is it talking about the jellyfish?-- 19:57, 27 May 2019 (UTC)

not any more Boatster (talk) 13:43, 28 May 2019 (UTC)

This panel is approximately 4.047 times as tall as it is wide. Moosenonny10 (talk) 00:19, 28 May 2019 (UTC)

I don't agree it's an entirely irrational fear -- it's much easier to rescue a drowned person from the lake/ocean bottom if the water is shallow. 07:50, 28 May 2019 (UTC)

It is still irrational – if someone's drowned at the bottom it isn't rescue anymore, just potentially recovering a dead body. Completely irrelevant for the unfortunate swimmer, unless she is worried about her family's emotions and the amount of (not entirely rational) public expense – all these expert divers, rescue units time, police work etc. cost a lot. -- Malgond (talk) 08:19, 28 May 2019 (UTC)
disagree. My sister rescued an unconscious kid from the bottom of a 3m deep pool. Rescuscitated him. Full recovery. Not common but it happens.Boatster (talk) 13:36, 28 May 2019 (UTC)
I believe that very deep waters are occasionally (and more frequently than shallow ones) dangerous due to cold undercurrents, so I support "not entirely irrational fear".Jkrstrt (talk) 08:59, 28 May 2019 (UTC)
Furthermore, on the topic of the specific fear in the comic, it's perfectly rational to be afraid of the ground you are relying on for support to suddenly and precipitously drop orders of magnitude deeper. Presumably the issue is not the irrationality of the fear but the language used - that is, "swimming" should be "wading" since their "feet touch bottom". Someone wading who was incapable of swimming would be rightfully afraid of suddenly being dropped into open sea, as they'd have limited ability to make it back to safety. 18:16, 28 May 2019 (UTC)

Back when I was teaching beginning swimming for adults, I would tell them that the deep end of the pool was better for swimming because there was more water under them to support them. Some of them found that the idea inspired confidence . . . others, not so much. 17:22, 28 May 2019 (UTC)

My wife is learning to swim at the moment (she's 50, never too old to learn!) and has this specific issue about being able to touch the bottom. She was told by her instructor about the deep end being "better for swimming" and definitely falls into the "not so much" category you mention!Daemonik (talk) 14:38, 29 May 2019 (UTC)
there is a way in which this is correct, and not trivially. Deeper pools cause less reflected turbulence to impede the swimmer so are marginally faster. Most international competition is now held in pools of uniform depth of, i think, at least 3 metres Boatster (talk) 05:26, 30 May 2019 (UTC)

What is the Lemmings reference mentioned in the explanation? Herobrine (talk) 12:18, 29 May 2019 (UTC)

Thank you, herobrine. My question exactly! Ianrbibtitlht (talk) 16:07, 29 May 2019 (UTC)
I would guess it is to the Lemmings (video game), I put in wikilink assuming that that is what is meant. Not sure though. 18:05, 29 May 2019 (UTC)I thought this was a global warming reference at first glance. it works pretty well as one. 03:19, 30 May 2019 (UTC)
Quite right. As someone old enough to remember Lemmings (video game), one of the tools to keep your lemmings from dying from a fall was an umbrella. Observer of the Absurd (talk) 21:53, 2 June 2019 (UTC)
As someone who played and loved the Lemmings games back in the day, at first I actually wondered at the claimed connection for a second until it clicked. For the uninitiated: the titular creatures simply walk. Blindly, unendingly. If their ground or floor ends (such as if there were no water here and they were walking to the right past Megan), they simply fall, and if they fall far enough (about the height of 3 lemmings, a LOT shorter than this cliff), they die with a splat. The point of the game is to assign jobs and abilities to them to survive / save everybody. One ability is to give them an umbrella, which they use on any significant drop to land softly and safely. Another ability is the reverse, to climb, such as if they were walking left from the umbrella they could climb to Megan. Assigning both makes the game call that particular lemming Athlete. :) If this were a level of Lemmings, the solution would be to make the first one a Miner (dig diagonally downwards, from off panel, further up the beach than the height of the cliff) then give umbrellas to anyone who walked past him before he got deep enough to cut off access to the cliff edge. Eventually there would be a gentle slope down to the lower shelf. NiceGuy1 (talk) 03:05, 8 June 2019 (UTC)

When I saw this, one element of it immediately reminded of a 26th/May BBC article that just barely preceded the comic's appearance. So maybe part of the fear is actually that of pellebaphobia. (Pellebathophobia, even?) 20:54, 30 May 2019 (UTC)