# 53 bicycles: A lateral thinking puzzle **URL:** \ **Category:** Thread Games\ **Created:** [July 9, 2017, 7:51pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868 "2017-07-09T19:51:32Z")\ **Posts on this page:** 20\ **Page:** 132
**Author:** ![Mahaloth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mahaloth/32/1079_2.png) [@Mahaloth](https://boards.straightdope.com/u/Mahaloth)\ **Post date:** [February 28, 2018, 3:41am UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2621 "2018-02-28T03:41:10Z")
> [@Chronos](#): > > OK, I just looked at **Mahaloth** ’s spoiler, and I’m pretty sure that’s it. My brain kept dancing around that, too, but for some reason just never alit on it. I hope so. I literally was cycling through “eggs” and weapons and landed on it. I must have read either a Straight Dope thread or article years ago and it fell into place. If it is wrong, it’s a pretty satisfying alternate solution. I’m pretty sure my understanding is correct and fits. ---
**Author:** ![Biotop](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/biotop/32/321_2.png) [@Biotop](https://boards.straightdope.com/u/Biotop)\ **Post date:** [February 28, 2018, 4:29am UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2622 "2018-02-28T04:29:54Z")
> [@Mahaloth](#): > > I hope so. I literally was cycling through “eggs” and weapons and landed on it. I must have read either a Straight Dope thread or article years ago and it fell into place. If it is wrong, it’s a pretty satisfying alternate solution. I’m pretty sure my understanding is correct and fits. [You got it!](http://knowledgenuts.com/2014/01/08/humpty-dumpty-was-a-cannon-not-an-egg/) ---
**Author:** ![Knowed\_Out](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/knowed_out/32/7380_2.png) [@Knowed\_Out](https://boards.straightdope.com/u/Knowed_Out)\ **Post date:** [February 28, 2018, 1:04pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2623 "2018-02-28T13:04:51Z")
Good one. Now I know something new. ---
**Author:** ![IvoryTowerDenizen](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ivorytowerdenizen/32/17937_2.png) [@IvoryTowerDenizen](https://boards.straightdope.com/u/IvoryTowerDenizen)\ **Post date:** [February 28, 2018, 1:11pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2624 "2018-02-28T13:11:05Z")
Wow! Very nice, indeed. ---
**Author:** ![Mahaloth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mahaloth/32/1079_2.png) [@Mahaloth](https://boards.straightdope.com/u/Mahaloth)\ **Post date:** [February 28, 2018, 8:32pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2625 "2018-02-28T20:32:06Z")
**Gabe worked in a factory and one day, he decided to inspect the inside of a tank that had only been used to hold fresh water. It was upright and had a manhole entry in the top. It was 4 meters deep and had a diameter of 2 meters. There was 15 cm of water on the bottom. Shortly after entering the tank, he keeled over and died. Why?** ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [February 28, 2018, 8:38pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2626 "2018-02-28T20:38:43Z")
Was his death caused by his entry into the tank? Did he drown? Did he asphyxiate? Did he die due to temperature extremes? Was the water liquid? ---
**Author:** ![Mahaloth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mahaloth/32/1079_2.png) [@Mahaloth](https://boards.straightdope.com/u/Mahaloth)\ **Post date:** [February 28, 2018, 8:49pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2627 "2018-02-28T20:49:56Z")
> [@Chronos](#): > > Was his death caused by his entry into the tank? NO > Did he drown? NO > Did he asphyxiate? YES > Did he die due to temperature extremes? NO > Was the water liquid? YES kk ---
**Author:** ![Folly](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/folly/32/3219_2.png) [@Folly](https://boards.straightdope.com/u/Folly)\ **Post date:** [February 28, 2018, 9:23pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2628 "2018-02-28T21:23:50Z")
Was there an unexpected amount of Nitrogen?, Argon?, Helium?, Butane?, Propane?, Carbon Dioxide? in the tank? If not, was there an unexpected amount of some other gas in the tank? An unusually low amount of oxygen in the tank? ---
**Author:** ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)\ **Post date:** [February 28, 2018, 10:44pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2629 "2018-02-28T22:44:47Z")
Did he close the top? Did someone else close the top? Did the top automatically close for some reason? ---
**Author:** ![Mahaloth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mahaloth/32/1079_2.png) [@Mahaloth](https://boards.straightdope.com/u/Mahaloth)\ **Post date:** [February 28, 2018, 11:07pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2630 "2018-02-28T23:07:03Z")
> [@Folly](#): > > Was there an unexpected amount of Nitrogen?, Argon?, Helium?, Butane?, Propane?, Carbon Dioxide? in the tank? > > NO TO ALL ABOVE > > If not, was there an unexpected amount of some other gas in the tank? NO An unusually low amount of oxygen in the tank? YES > [@Quartz](#): > > Did he close the top? IRRELEVANT > Did someone else close the top? IRRELEVANT > Did the top automatically close for some reason? IRRELEVANT KK ---
**Author:** ![Walken\_After\_Midnight](https://avatars.discourse-cdn.com/v4/letter/w/b487fb/32.png) [@Walken\_After\_Midnight](https://boards.straightdope.com/u/Walken_After_Midnight)\ **Post date:** [February 28, 2018, 11:22pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2631 "2018-02-28T23:22:44Z")
Did temperature play any part in this incident? ---
**Author:** ![Mahaloth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mahaloth/32/1079_2.png) [@Mahaloth](https://boards.straightdope.com/u/Mahaloth)\ **Post date:** [February 28, 2018, 11:24pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2632 "2018-02-28T23:24:17Z")
> [@Walken\_After\_Midnight](#): > > Did temperature play any part in this incident? No. ---
**Author:** ![Folly](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/folly/32/3219_2.png) [@Folly](https://boards.straightdope.com/u/Folly)\ **Post date:** [February 28, 2018, 11:27pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2633 "2018-02-28T23:27:01Z")
Was there low oxygen due to a chemical reaction? Was there low oxygen due to absorption by a substance of the oxygen? (Which I guess is also a chemical reaction) Did a physical mechanism cause there to be low oxygen? Did a non-human living substance/creature create a low oxygen environment? ---
**Author:** ![Mahaloth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mahaloth/32/1079_2.png) [@Mahaloth](https://boards.straightdope.com/u/Mahaloth)\ **Post date:** [February 28, 2018, 11:47pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2634 "2018-02-28T23:47:40Z")
> [@Folly](#): > > Was there low oxygen due to a chemical reaction? YES > > Was there low oxygen due to absorption by a substance of the oxygen? (Which I guess is also a chemical reaction) NO > > Did a physical mechanism cause there to be low oxygen? I’m not sure what you mean. > > Did a non-human living substance/creature create a low oxygen environment? NO kk ---
**Author:** ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)\ **Post date:** [February 28, 2018, 11:51pm UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2635 "2018-02-28T23:51:55Z")
Had Gabe been walking in something before entering the tank? Did it stick to his boots or clothing? Did that something react with the water drawing the oxygen out of the air? Was Gabe smoking? ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [March 1, 2018, 12:12am UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2636 "2018-03-01T00:12:32Z")
Did the tank contain normal oxygen levels as of when Gabe entered it? By “normal”, I mean levels typical of sea level outside on Earth. And a physical mechanism causing low oxygen could, for instance, be a vacuum pump. ---
**Author:** ![Mahaloth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mahaloth/32/1079_2.png) [@Mahaloth](https://boards.straightdope.com/u/Mahaloth)\ **Post date:** [March 1, 2018, 12:35am UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2637 "2018-03-01T00:35:36Z")
> [@Quartz](#): > > Had Gabe been walking in something before entering the tank? Did it stick to his boots or clothing? Did that something react with the water drawing the oxygen out of the air? > > Was Gabe smoking? No to all. > [@Chronos](#): > > Did the tank contain normal oxygen levels as of when Gabe entered it? NO > > By “normal”, I mean levels typical of sea level outside on Earth. NO > > And a physical mechanism causing low oxygen could, for instance, be a vacuum pump. NO kk ---
**Author:** ![Biotop](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/biotop/32/321_2.png) [@Biotop](https://boards.straightdope.com/u/Biotop)\ **Post date:** [March 1, 2018, 1:28am UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2638 "2018-03-01T01:28:07Z")
Was Gabe on Earth? ---
**Author:** ![Mahaloth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mahaloth/32/1079_2.png) [@Mahaloth](https://boards.straightdope.com/u/Mahaloth)\ **Post date:** [March 1, 2018, 1:32am UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2639 "2018-03-01T01:32:37Z")
> [@Biotop](#): > > Was Gabe on Earth? Yes. ---
**Author:** ![IvoryTowerDenizen](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ivorytowerdenizen/32/17937_2.png) [@IvoryTowerDenizen](https://boards.straightdope.com/u/IvoryTowerDenizen)\ **Post date:** [March 1, 2018, 1:34am UTC](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868/2640 "2018-03-01T01:34:33Z")
Was the tank under pressure when he entered? [Previous page](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868.md?page=131) [Next page](https://boards.straightdope.com/t/53-bicycles-a-lateral-thinking-puzzle/790868.md?page=133)