# Temperature Scales **URL:** \ **Category:** Cecil's Columns/Staff Reports\ **Created:** [December 17, 1999, 1:56am UTC](https://boards.straightdope.com/t/temperature-scales/447 "1999-12-17T01:56:00Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![The\_Ryan](https://avatars.discourse-cdn.com/v4/letter/t/7feea3/32.png) [@The\_Ryan](https://boards.straightdope.com/u/The_Ryan)\ **Post date:** [December 17, 1999, 6:10am UTC](https://boards.straightdope.com/t/temperature-scales/447/1 "1999-12-17T06:10:00Z")
In the column [http://www.straightdope.com/classics/a4\_188.html](http://www.straightdope.com/classics/a4_188.html) Cecil gives the oft-quoted value of 98.6 for the temperature of humans. Are three significant digits really appropiate? ---
**Author:** ![WhizBang](https://avatars.discourse-cdn.com/v4/letter/w/c5a1d2/32.png) [@WhizBang](https://boards.straightdope.com/u/WhizBang)\ **Post date:** [December 17, 1999, 1:56am UTC](https://boards.straightdope.com/t/temperature-scales/447/2 "1999-12-17T01:56:00Z")
Any midwestern kid understands the sensibility and utility of the Fahrenheit scale: Any weather above 100 or below zero means that school is cancelled. What could be easier? ---
**Author:** ![RM\_Mentock](https://avatars.discourse-cdn.com/v4/letter/r/e274bd/32.png) [@RM\_Mentock](https://boards.straightdope.com/u/RM_Mentock)\ **Post date:** [December 17, 1999, 4:30am UTC](https://boards.straightdope.com/t/temperature-scales/447/3 "1999-12-17T04:30:00Z")
Yep, 98.6F is the same as 37C, which is only two significant figures, as it was when the study was done originally, as I understand it. Are you sure Cecil never commented about this? I thought that’s where I learned it. Drop him a line. Of course, 98.6 has become iconic. ---
**Author:** ![RM\_Mentock](https://avatars.discourse-cdn.com/v4/letter/r/e274bd/32.png) [@RM\_Mentock](https://boards.straightdope.com/u/RM_Mentock)\ **Post date:** [December 17, 1999, 4:39am UTC](https://boards.straightdope.com/t/temperature-scales/447/4 "1999-12-17T04:39:00Z")
Well, hell, I just looked up another reference, and it says that average human body temperature is in the range 98.4F to 98.6F, so maybe three significant figures is justified. ---
**Author:** ![Phillies\_Phan](https://avatars.discourse-cdn.com/v4/letter/p/b2d939/32.png) [@Phillies\_Phan](https://boards.straightdope.com/u/Phillies_Phan)\ **Post date:** [December 17, 1999, 3:17pm UTC](https://boards.straightdope.com/t/temperature-scales/447/5 "1999-12-17T15:17:00Z")
The real reason the temperature scale is 32 and 212: Farenheit was using the freezing and boiling points of _salt_ water. Salt water freezes at 0 and boils at 180. I’m not sure why 180 was chosen for the freezing point bu it is one half of the number of degrees in a circle (a semi-circle if you will). The circle is a perfect geometric shape, so this might be the reason. John T. * * * Alone we can move buckets; together we can drain rivers.–Mike Brady, from the Brady Bunch movie ---
**Author:** ![the\_Scarlet\_Pimpernel](https://avatars.discourse-cdn.com/v4/letter/t/f1d935/32.png) [@the\_Scarlet\_Pimpernel](https://boards.straightdope.com/u/the_Scarlet_Pimpernel)\ **Post date:** [December 18, 1999, 3:49pm UTC](https://boards.straightdope.com/t/temperature-scales/447/7 "1999-12-18T15:49:00Z")
Midwesterners close the schools if the temperature cranks up above 100? Hell, where I went to school we didnt even notice it was warm until it got up above 105. But then, if it got below 50 we all thought we would die of frostbite. 🙂 * * * the Artist Formerly Known as Kara ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [December 19, 1999, 1:08am UTC](https://boards.straightdope.com/t/temperature-scales/447/8 "1999-12-19T01:08:00Z")
[Farenheit was using the freezing and boiling points of salt water. Salt water freezes at 0 and boils at 180. I’m] the freezing pt. of a mixture of salt and water will vary according to the quantities of each. sea water will freeze at a temp closer to 32 then 0, I think it is 28, but not sure. I do know that a canal on the inside of a barier reef island that I used to live along would freeze when temps were above 0, usally in the teens, sometimes in the 20’s depending on factios as sun/wind/current. now admittaly the water was not exactly sea water since it is an estuary, but it is pretty close. Also I would thing that salt water would have a higher boiling point then fresh. ---
**Author:** ![Polycarp](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Polycarp](https://boards.straightdope.com/u/Polycarp)\ **Post date:** [December 23, 1999, 7:22pm UTC](https://boards.straightdope.com/t/temperature-scales/447/9 "1999-12-23T19:22:00Z")
0 Fahrenheit was quasi-arbitrary. IIRC, he was looking for a temperature that could be created but lower than which ambient temperature was not likely to go. Obviously, in the winter it got below the freezing point of water; it might even get below the freezing point of seawater. What he set 0 at was the freezing point of a specific-proportion brine mixture. Exact components escape me, but it was **not** seawater but a more concentrated brine, with some other “antifreeze” component included. ---
**Author:** ![Jinx](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jinx](https://boards.straightdope.com/u/Jinx)\ **Post date:** [December 30, 1999, 2:41pm UTC](https://boards.straightdope.com/t/temperature-scales/447/10 "1999-12-30T14:41:00Z")
Regarding the remark on boiling a salt solution at 180 (dgrs F - I assume). A saline solution boiling at 180 F? Not true! A solute surpresses the boiling point, thus the boiling point of any solution is elevated above the normal boiling point of the pure solvent. (Normal boiling point refers to boiling at atmospheric pressure.) Hence, a salt solution will boil above 212 F. And, if curious, the steam coming off a salt solution will be superheated steam because the temp of the water vapor is now raised above the normal boiling point. The parallel drawn between 180 dgrs in a semi-circle is bogus. …But, don’t get all steamed up over this! * * * I’d rather have a bottle in front of me than a frontal lobotomy - Hawkeye 4077th ---
**Author:** ![Jinx](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jinx](https://boards.straightdope.com/u/Jinx)\ **Post date:** [January 5, 2000, 1:30pm UTC](https://boards.straightdope.com/t/temperature-scales/447/11 "2000-01-05T13:30:00Z")
Slight Correction to above: I meant to say “surpresses boiling” thus raising the normal boiling point. I hope you got the gist! * * * I’d rather have a bottle in front of me than a frontal lobotomy - Hawkeye 4077th ---
**Author:** ![Diceman](https://avatars.discourse-cdn.com/v4/letter/d/22d042/32.png) [@Diceman](https://boards.straightdope.com/u/Diceman)\ **Post date:** [January 5, 2000, 3:18pm UTC](https://boards.straightdope.com/t/temperature-scales/447/12 "2000-01-05T15:18:00Z")
Not to nitpick, but you mean “boiling point **elevation** ”. The freezing point is what is supressed by a solute. * * * “I had a feeling that in Hell there would be mushrooms.” -The Secret of Monkey Island ---
**Author:** ![Jinx](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jinx](https://boards.straightdope.com/u/Jinx)\ **Post date:** [January 5, 2000, 3:33pm UTC](https://boards.straightdope.com/t/temperature-scales/447/13 "2000-01-05T15:33:00Z")
My thanks to Diceman on the subtle clarification. Yes, freezing point is suppressed and the boiling point of a solution is elevated by a solute. However, {see my submitted correction}, it is also correct to say that the physical ACT of boiling a solution is suppressed by a solute. In the field, it’s quickly spoken of as “boiling is suppressed” which implicitly includes the fact that the boiling point is elevated. Hope this helps clarify! * * * I’d rather have a bottle in front of me than a frontal lobotomy - Hawkeye 4077th ---
**Author:** ![galt](https://avatars.discourse-cdn.com/v4/letter/g/35a633/32.png) [@galt](https://boards.straightdope.com/u/galt)\ **Post date:** [January 18, 2000, 8:37am UTC](https://boards.straightdope.com/t/temperature-scales/447/14 "2000-01-18T08:37:00Z")
Tangentially, how do you interpret “turn down the air conditioner”? 🙂 ---
**Author:** ![Irishman](https://avatars.discourse-cdn.com/v4/letter/i/b487fb/32.png) [@Irishman](https://boards.straightdope.com/u/Irishman)\ **Post date:** [January 19, 2000, 5:10pm UTC](https://boards.straightdope.com/t/temperature-scales/447/15 "2000-01-19T17:10:00Z")
I ask the person if they want it colder or warmer. ---
**Author:** ![drewder](https://avatars.discourse-cdn.com/v4/letter/d/57b2e6/32.png) [@drewder](https://boards.straightdope.com/u/drewder)\ **Post date:** [April 6, 2016, 2:59am UTC](https://boards.straightdope.com/t/temperature-scales/447/16 "2016-04-06T02:59:04Z")
The inventors of penicillin, the polio vaccine, and DDT. ---
**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:** [April 6, 2016, 10:56am UTC](https://boards.straightdope.com/t/temperature-scales/447/17 "2016-04-06T10:56:28Z")
What in the world was that about, **drewder**? ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [April 6, 2016, 11:18am UTC](https://boards.straightdope.com/t/temperature-scales/447/18 "2016-04-06T11:18:20Z")
Sounds like a Carnac question… ---
**Author:** ![drewder](https://avatars.discourse-cdn.com/v4/letter/d/57b2e6/32.png) [@drewder](https://boards.straightdope.com/u/drewder)\ **Post date:** [April 6, 2016, 12:21pm UTC](https://boards.straightdope.com/t/temperature-scales/447/19 "2016-04-06T12:21:49Z")
> [@Chronos](#): > > What in the world was that about, **drewder**? Somehow got posted to the wrong thread. Odd because I don’t think I have ever looked at this thread before.