How do you make ice without electricity?

[vicars]

I seem to remember that salt is a part of the process but any ideas?

[Mattk]

water and sub zero temperatures !

[NiceCupOfTea]

Not sure how salt comes into making ice? When you add salt to water it actually lowers the freezing point of water, hence we put it on pavements to stop ice forming.

[mibn2cweus]

I seem to remember that salt is a part of the process to melt ice to make ice cream freeze more quickly in an ice cream maker?

[stanleyman]

Is this what you mean?

http://www.canalmuseum.org.uk/education/victorian/popupe 8s7.htm

[stanleyman]

This link doesn't seem to work now! It was about Victorian ice makers using ether and other chemicals with a steam powered machine. They used salt water cooled to below freezing in which ice moulds were placed containing fresh water, this of course froze to form the ice blocks.

Much easier in the freezer!

[vicars]

Thanks stan, when you click on the link you have to delete the last 3 or 4 'added' characters that appear. I think the salt relates to making ice cream, so I guess I'll just have to amaze my friends with ice cubes from the freezer. Thanks for the replies.

[buildersmate]

The technical answer is this.

When ice melts, it absorbs heat from its surroundings. This is called latent heat of fusion. The temperature of the ice / water mix remains at 0 degrees until enough heat has been absorbed to melt all the ice. If salt is added to ice, it tries to lower its melting point but the ice still needs to take in energy from the surroundings to satisfy the latent heat of fusion. If you surround a metal container of cold water with ice/salt mix, the mix extracts the latent heat it needs from the pure water and freezes it.

[Gef]

buildersmate's answer is technically correct but where do you get the ice from in the first place?

[fuzzibear]

Go to the highlands in Scotland, and there will be as much as you can carry in Winter, all without the need for electricity.

[Mayweewee]

whatever