# In praise of the magic Thermos - It keeps hot things hot and cold things cold! **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [November 16, 2002, 1:30pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019 "2002-11-16T13:30:09Z")\ **Posts on this page:** 16\ **Page:** 1
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [November 16, 2002, 1:30pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/1 "2002-11-16T13:30:09Z")
My First Thermos! I’ve never owned a real Thermos. I’ve had the occasional insulated travel mug, but they just kept my fingers from getting burned and the coffee from spilling. I was rooting around at Staples the other day and there were some Thermos brand thermos travel mug on clearance so I decided to get one. It has a brushed stainless steel body with a plastic top and a sort of internal rubber flange on the screw down lid with a sipping hole. The bottom has a wide base for stability. I’m a fairly jaded citizen of the new Millennium and I’ve got a lot of techno tools and toys but this thing is the bomb! I can put in piping hot coffee and it’s still hot 30 minutes later - an hour later - two hours later!! Usually my coffee is cold in 15 -20 minutes or so. It’s like magic! This thing amazes me more than a high end notebook computer. I’m not exactly sure how it works, but’s cool on the outside steel shell even with piping hot coffee inside so I’m pretty sure some powerful mojo is involved. Hot things stay hot and cold things stay cold. It’s amazing! ---
**Author:** ![haardvark](https://avatars.discourse-cdn.com/v4/letter/h/b5ac83/32.png) [@haardvark](https://boards.straightdope.com/u/haardvark)\ **Post date:** [November 16, 2002, 1:46pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/2 "2002-11-16T13:46:14Z")
“but, how does it KNOW?” ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [November 16, 2002, 2:02pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/3 "2002-11-16T14:02:31Z")
Dammit, **haardvark**! I was going to say that! ---
**Author:** ![BlueMoonofKentucky](https://avatars.discourse-cdn.com/v4/letter/b/8dc957/32.png) [@BlueMoonofKentucky](https://boards.straightdope.com/u/BlueMoonofKentucky)\ **Post date:** [November 16, 2002, 2:43pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/4 "2002-11-16T14:43:02Z")
It’s supposed to keep the hot stuff hot and cold stuff cold, right? So I put in a cup of coffee and a popsicle ---
**Author:** ![Eonwe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eonwe/32/240_2.png) [@Eonwe](https://boards.straightdope.com/u/Eonwe)\ **Post date:** [November 16, 2002, 3:58pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/5 "2002-11-16T15:58:51Z")
[Steve Martin] _I’m picking out a Thermos, for you… not an ordinary Thermos, will do…_ [/Steve Martin] ---
**Author:** ![SwimmingRiddles](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@SwimmingRiddles](https://boards.straightdope.com/u/SwimmingRiddles)\ **Post date:** [November 16, 2002, 6:06pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/6 "2002-11-16T18:06:42Z")
I still remember the magic of my Rainbow Brite lunchbox/thermos. The coolness of the thermos was usually negated by the fact that it contained tomato soup, though. ---
**Author:** ![TVGuy](https://avatars.discourse-cdn.com/v4/letter/t/82dd89/32.png) [@TVGuy](https://boards.straightdope.com/u/TVGuy)\ **Post date:** [November 16, 2002, 6:15pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/7 "2002-11-16T18:15:59Z")
Wait. Wasn’t the McDLT supposed to keep the hot side hot and cold side cold? Hail to your commercially available Dewar Flask!! ---
**Author:** ![asterion](https://avatars.discourse-cdn.com/v4/letter/a/4da419/32.png) [@asterion](https://boards.straightdope.com/u/asterion)\ **Post date:** [November 16, 2002, 7:19pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/8 "2002-11-16T19:19:55Z")
Yep, nothing like a vacuum/near vacuum to insulate and prevent heat transfer. ---
**Author:** ![haardvark](https://avatars.discourse-cdn.com/v4/letter/h/b5ac83/32.png) [@haardvark](https://boards.straightdope.com/u/haardvark)\ **Post date:** [November 17, 2002, 4:33am UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/9 "2002-11-17T04:33:01Z")
> [@](#): > > \*Originally posted by TVGuy \* > **Wait. Wasn’t the McDLT supposed to keep the hot side hot and cold side cold?** I worked at the Arches for most of Highschool and the McDLT was still big then. I made the damn things and I never understood: we put the cool stuff in one side of a styrofoam tray, next to the hot burger on the other side…_and then slid both sides onto the heat rack, where the package would sit for several minutes before purchase_. Cursory experiments indicated that the cool side wasn’t, unless you bought the thing **immediately**. other experiments included making exploding shuriken out of cheese slices and mustard, but that’s another story… ---
**Author:** ![donkeyoatey](https://avatars.discourse-cdn.com/v4/letter/d/e47c2d/32.png) [@donkeyoatey](https://boards.straightdope.com/u/donkeyoatey)\ **Post date:** [November 17, 2002, 4:49am UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/10 "2002-11-17T04:49:39Z")
> [@](#): > > \*Originally posted by asterion \* > \*\*Yep, nothing like a vacuum/near vacuum to insulate and prevent heat transfer. \*\* My mom asked me to bring over our Electolux cause hers was broken. And the wife just made a huge pot soup chicken soup for supper and I thought I’d be a nice son and bring mom some. So I put some in the Electolux before I left. Damn it. Buy a Thermos you say?🙂 ---
**Author:** ![hawthorne](https://avatars.discourse-cdn.com/v4/letter/h/c89c15/32.png) [@hawthorne](https://boards.straightdope.com/u/hawthorne)\ **Post date:** [November 17, 2002, 11:57am UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/11 "2002-11-17T11:57:31Z")
When did the insides stop being so fragile? I recall the inserts used to be glass and they would break very easily. My new brushed-steel model seems much more robust. ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [November 17, 2002, 2:19pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/12 "2002-11-17T14:19:58Z")
I had a thermos SS travel cup a while back - I lost it along the way - i think this thread just encougaged me to get a new one. ---
**Author:** ![TVGuy](https://avatars.discourse-cdn.com/v4/letter/t/82dd89/32.png) [@TVGuy](https://boards.straightdope.com/u/TVGuy)\ **Post date:** [November 17, 2002, 9:41pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/13 "2002-11-17T21:41:05Z")
**Astro** - I finally dug up the link that I wanted to post earlier about the amazing and wonderful [Sir James Dewar](http://inventors.about.com/library/inventors/blthermos.htm) - inventor of the appropriately named Dewar flask, or bottle, or your case, the Thermos! ---
**Author:** ![Cyrin](https://avatars.discourse-cdn.com/v4/letter/c/eb8c5e/32.png) [@Cyrin](https://boards.straightdope.com/u/Cyrin)\ **Post date:** [December 4, 2002, 7:08pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/14 "2002-12-04T19:08:58Z")
A construction worker was browsing through walmart when he came across the Thermos section. He asked a nearby associate what these things were. “It’s a Thermos” “What’s that?” “Oh it’s great! It keeps hot things hot, and keeps cold things cold!” “That’s amazing! How does it do that?” “Magic.” “Wow! I have to have one!” So he purchased one and brought it to the construction site the next day. “What’s that?” asked a fellow construction worker “It’s a thermos!” “Oh ya? What does it do?” “Oh it’s great! It keeps hot things hot, and cold things cold!” “Really? How does it do that?” “Magic!” “Wow! What do you have in it?” “Soup! and a popsicle!” 😃 ---
**Author:** ![Siemsi](https://avatars.discourse-cdn.com/v4/letter/s/b19c9b/32.png) [@Siemsi](https://boards.straightdope.com/u/Siemsi)\ **Post date:** [December 4, 2002, 7:14pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/15 "2002-12-04T19:14:21Z")
haardvark Love that joke/punchline!😃 ---
**Author:** ![Barbarian](https://avatars.discourse-cdn.com/v4/letter/b/e19adc/32.png) [@Barbarian](https://boards.straightdope.com/u/Barbarian)\ **Post date:** [December 4, 2002, 8:52pm UTC](https://boards.straightdope.com/t/in-praise-of-the-magic-thermos-it-keeps-hot-things-hot-and-cold-things-cold/137019/16 "2002-12-04T20:52:40Z")
One of the first prezzies that MrsB bought me (back when we were still dating) was a Thermos. It was blue, and she got big black letters with my name put on it. She’d put hot chocolate in it to keep me warm on my winter drive home. Good thing our love lasted longer than the thermos did! Does anyone know if there’s a thermos that will fit in your bike bottle rack?