This form of divination used barley to determine whether someone was guilty or innocent of a crime. A specially-prepared barley or wheat loaf or cake was fed to the suspect. If the accused ate the loaf without ill effects, they were innocent. On the other hand, if the accused choked, refused to eat, found the loaf inedible, or even got a rumbly stomach afterwards, they were surely guilty.
Medieval English law used a similar technique, called “cursed bread” or corsned. In a similar fashion, innocent parties would enjoy a nice piece of bread, while the guilty would suffer. Since barley bread was harder to chew, it increased the risk of choking.
In England, the Earl of Wessex took the corsned test to defend himself against allegations of a false oath. When he died a few days later, many pointed to alphitomancy as a form of divine prophecy.
This technique was also effective when there were several suspects. All suspects were provided with barley bread, which they believed could only be eaten easily by the innocent.
The bread had to be carefully created and administered in order to be effective. Bartley was mixed with milk and a little salt. The bread dough was rolled in greased paper and baked among the coals. Once it was cooked, the bread was removed and rolled in verbena leaves. Pieces of the bread were distributed among the suspects. The innocent were easily weeded out, as they could eat it with no harm.
Over time, this form of divination became so important that it was used for a variety of crimes. It was even used to check the faithfulness of husbands and wives, mistresses and lovers.
In Roman times, alphitomancy was also used to test the purity of young women. In a nearby forest, priests lived with their serpent in a cavern. In some tales, they have a dragon instead. At certain times of the year, young women were blindfolded and sent down a trail carrying cakes made of barley flour and honey. The serpent would eat cakes carried by the innocent, while refusing the cakes of the guilty.