Today's kid's cereals are almost sweet enough to qualify as candy (especially the ones containing little marshmallows, which were my favorite), but that's not what I'm talking about. Barley sugar was a favorite Victorian treat that was especially popular at Christmas. It was originally made from sugar boiled in water in which barley had previously been boiled, which produced a hard amber-colored candy. It was often consumed as a soothing throat lozenge.
Barley sugar is also called barley candy or barley sugar candy, although sometimes a distinction is made. Timberlake Candies, which produces handmade barley candy, says the difference is that barley sugar is made with cream of tartar, while barley candy is made without it but with corn syrup, which produces a harder, clearer product. Starting in the 18th century, metal molds were used to create colorful, remarkably detailed candy toys. A number of American companies continue to make these old-fashioned novelties, with or without actual barley water.
According to The Glutton's Glossary, by John Ayto, barley sugar was traditionally made into long, twisted sticks, so "barley-sugar" came to be used an architectural term for twisted columns.
The Wikipedia entry on barley sugar suggests that barley candy arose as a linguistic misunderstanding between the French and the English. The French brought sucre brûlé, or burnt sugar, to England, who mistranslated it as "barley sugar." This was then retranslated into the French as sucre d'orge, literally barley sugar. I'm skeptical that the story is true, but I'm a sucker (no pun intended) for etymological legends.
In any case, today you can visit the Musée du Sucre d'Orge, in Moret-Sur-Loing, southeast of Paris, where you can watch the confection being made and learn about the Benedictine nuns who made it. Although the nuns stopped production in the 1970s, they passed their recipe on to a local family that continues to make the heart-shaped candies stamped with a cross, which are packaged in an adorable tin.