The American forefathers didn't drink many other alcoholic drinks than fermented cider or its stronger brother Apple Jack. Beer was not popular in this country until large waves of German settlers came in the mid to late 1800's.
Their method of making Apple Jack was to leave wooden barrels of fermented cider outside in the winter to freeze and scooping out the formed ice until the remaining liquid didn't freeze. Water makes up the majority of beer to wine strength alcoholic beverages and as you remove more and more water the freezing temperature lowers. Jacking will not remove all of the water, so your Apple Jack will not be able to get stronger than around 20% alcohol depending on how cold your freezer gets.
While it is illegal to distill alcohol in this country, it is NOT illegal to Jack your cider. According to the government the act of distilling requires that you remove alcohol, which is illegal. Jacking requires that you remove the water, so it counts as concentrating a beverage making it different than distillation.
The best way I have found to jack my cider is to poke 20 or so holes in the lid of a plastic 1 gallon water jug and fill it with cider then put it in the freezer. Pull it out of the freezer every couple of hours and shake it up (while covering the holes in the lid obviously). Shaking it will help separate the tiny ice crystals from the compounds that will not freeze and and concentrate the ice together since it is easier for ice to bond to other crystals of formed ice than to unfrozen water. If you do not shake it the ice crystals will form around thousands of tiny pockets of unfrozen jack that you will not be able to separate from the ice.
After a day or so you will notice that your container is mostly frozen, take a large clean container and turn your jug upside down over it. Slowly your jack will run out leaving ice behind. Remove your jug when there is nothing but mostly white ice left.
An alternate way that doesn't require the use of plastic containers would be to place a stainless steel mixing bowl full of jack in the freezer and to scoop out the ice crystals every few hours with a fine screen food strainer or fish-net.
Your apple jack will be somewhere around twice as strong as the cider you started with.
There are alot of people around the internet that say this is bad for you because removing the water raises the level of the bad substances in fermented drinks that can give you hangovers and so on. They are idiots because if you were drinking 8 pints of regular strength cider or 4 pints of jack you would get the same drunk and get the same amounts of those bad substances. The amount of them you consume has not changed.
