# Ice Harvesting
**URL:** https://boards.straightdope.com/t/ice-harvesting/348739
**Category:** Cecil's Columns/Staff Reports
**Created:** [March 17, 2006, 2:30pm UTC](https://boards.straightdope.com/t/ice-harvesting/348739 "2006-03-17T14:30:49Z")
**Posts on this page:** 13
**Page:** 1
### Author:  [@muldoonthief](https://boards.straightdope.com/u/muldoonthief)
#### Post date: [March 17, 2006, 2:30pm UTC](https://boards.straightdope.com/t/ice-harvesting/348739/1 "2006-03-17T14:30:49Z")
I think there’s a typo (since it couldn’t be an error) in Cecil’s article about ice harvesting/sale. Describing ice houses:
> [@Cecil](#):
>
> An opening at the top vented the latent heat released by melting;
The problem is that latent heat is the heat/energy required to convert 0 ºC ice to 0 ºC water - it’s heat you add, not heat that’s released. [cite](http://www.physchem.co.za/Heat/Latent.htm).
> [@from linked site](#):
>
> This means that to convert 1 kg of ice at 0 ºC to 1 kg of water at 0 ºC, 334 kJ of heat must be absorbed by the ice.
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### Author:  [@muldoonthief](https://boards.straightdope.com/u/muldoonthief)
#### Post date: [March 17, 2006, 4:34pm UTC](https://boards.straightdope.com/t/ice-harvesting/348739/2 "2006-03-17T16:34:56Z")
Forgot link:
[How was ice made and sold in pre-industrial times?](http://www.straightdope.com/columns/060317.html)
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### Author:  [@spingears](https://boards.straightdope.com/u/spingears)
#### Post date: [March 17, 2006, 7:13pm UTC](https://boards.straightdope.com/t/ice-harvesting/348739/3 "2006-03-17T19:13:39Z")
> [@](#):
>
> _Cecil replies:_
> Don’t despair, Terwiliger. The ice business, like carburetor rebuilding or vinyl record manufacture, is one of those vanished (or mostly vanished) enterprises that baffles later generations. _If you think selling ice is nutty, ask some old engineering geek what it was like using a slide rule._
And I will tell you what is was like to use a 7 place table of logarithims!A slide rule is just fine for ordinary engineering calculations.
When higher precision is required you either have to get a 20 ft. slide rule with 4 signifigant digits or turn to logarithms.
To multiply you add and to divide you subtract, to raise to powers you multiply, and to extract roots you divide. Sounds confusing,doesn’t it?
And all the time keep track of the mantissas and the characteristic of each term.
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### Author:  [@Skammer](https://boards.straightdope.com/u/Skammer)
#### Post date: [March 17, 2006, 7:23pm UTC](https://boards.straightdope.com/t/ice-harvesting/348739/4 "2006-03-17T19:23:51Z")
> [@Cecil](#):
>
> The ice business, like carburetor rebuilding or vinyl record manufacture, is one of those vanished (or mostly vanished) enterprises that baffles later generations
That’s why I’ve put all my money in buggy whips!
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### Author:  [@CJJ](https://boards.straightdope.com/u/CJJ)
#### Post date: [March 17, 2006, 7:38pm UTC](https://boards.straightdope.com/t/ice-harvesting/348739/5 "2006-03-17T19:38:44Z")
> [@muldoonthief](#):
>
> I think there’s a typo (since it couldn’t be an error) in Cecil’s article about ice harvesting/sale…The problem is that latent heat is the heat/energy required to convert 0 ºC ice to 0 ºC water - it’s heat you _add_, not heat that’s released.
I would not presume to answer for the Master, but it is fairly clear that he intended to say the following: An opening at the top allowed evaporation (from the melted water clinging to the ice) to draw off any latent heat of melting that could melt the ice further (i.e. evaporation, encouraged by the vent, cooled the still-solid ice block). An obvious typo.
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### Author:  [@Skywatcher](https://boards.straightdope.com/u/Skywatcher)
#### Post date: [March 18, 2006, 12:10am UTC](https://boards.straightdope.com/t/ice-harvesting/348739/6 "2006-03-18T00:10:55Z")
> [@Cecil](#):
>
> Some nonelectrified rural areas relied on ice deliveries until the 50s, but eventually what had always been a faintly comical business melted away without a trace.
Yep. The last ice house in Kankakee County, Illinois, burned down in the early '70s–while it was being demolished.
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### Author:  [@AussieJohn](https://boards.straightdope.com/u/AussieJohn)
#### Post date: [March 18, 2006, 1:51am UTC](https://boards.straightdope.com/t/ice-harvesting/348739/7 "2006-03-18T01:51:40Z")
I remember the ice in hot Australian country towns in summer coming from icehouses which used evaporative cooling wooden water towers to make the ice. It seemed to work very well, with the water cascading down the outside.
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### Author:  [@Loopus](https://boards.straightdope.com/u/Loopus)
#### Post date: [March 18, 2006, 9:38pm UTC](https://boards.straightdope.com/t/ice-harvesting/348739/8 "2006-03-18T21:38:53Z")
This is just the kind of Cecil column I like. It answers an interesting question that I would have never thought to ask in an entertaining way.
I’m letting my SDMB subscription lapse next month, but I reckon I’ll keep reading Cecil’s columns as long as he can crank out ones like this.
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### Author:  [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)
#### Post date: [March 19, 2006, 4:05am UTC](https://boards.straightdope.com/t/ice-harvesting/348739/9 "2006-03-19T04:05:41Z")
> [@Skammer](#):
>
> That’s why I’ve put all my money in buggy whips!
The buggy whip industry is doing quite well.
Buggy driving nowdays (except for the Amish & similar) is nearly all for a hobby, and participating in horse shows & eventing.
People of the past, who used buggy driving as ordinary transportation, would spend as little as possible on buggy whips. But compared to them, people will spend much more on their hobby, on high-quality, fancy looking buggy whips. To say nothing on the spending on really fancy whips for shows!
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### Author:  [@spingears](https://boards.straightdope.com/u/spingears)
#### Post date: [March 21, 2006, 2:28pm UTC](https://boards.straightdope.com/t/ice-harvesting/348739/10 "2006-03-21T14:28:22Z")
> [@AussieJohn](#):
>
> I remember the ice in hot Australian country towns in summer coming from icehouses which used evaporative cooling wooden water towers to make the ice. It seemed to work very well, with the water cascading down the outside.
That is very interesting!
Wasn’t there some kind of refrigeration machinery that used the water from the evaporative cooling tower(s) to actually freeze the ice?
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### Author:  [@DRieger](https://boards.straightdope.com/u/DRieger)
#### Post date: [March 21, 2006, 8:21pm UTC](https://boards.straightdope.com/t/ice-harvesting/348739/11 "2006-03-21T20:21:50Z")
> [@CJJ\*](#):
>
> I would not presume to answer for the Master, but it is fairly clear that he intended to say the following: An opening at the top allowed evaporation (from the melted water clinging to the ice) to draw off any latent heat of melting that could melt the ice further (i.e. evaporation, encouraged by the vent, cooled the still-solid ice block). An obvious typo.
There is no “latent heat of melting” to further melt the ice. The change of state due to melting absorbs heat. I agree that evapororative cooling could have been the reason for the vents. Or perhaps a vent design that draws air along the surface of the roof to prevent it from becoming too hot.
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### Author:  [@saoirse](https://boards.straightdope.com/u/saoirse)
#### Post date: [March 22, 2006, 2:32am UTC](https://boards.straightdope.com/t/ice-harvesting/348739/12 "2006-03-22T02:32:19Z")
If there is a **Latent Heat of Condensation,** and I know that there is, because it is a term that was drilled into my head once, it stands to reason that there would also be a latent heat of freezing. Melting and evaporation would cause cooling, then.
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### Author:  [@Chronos](https://boards.straightdope.com/u/Chronos)
#### Post date: [March 22, 2006, 9:31pm UTC](https://boards.straightdope.com/t/ice-harvesting/348739/13 "2006-03-22T21:31:41Z")
Then, too, liquid water in the vicinity of the ice would have a tendancy to defeat the insulation and allow the ice to couple more efficiently with the ambient thermal environment. That ambient thermal environment being a hot summer’s day.