The Alchemist's Code

A B C D E F G H I J L M N O P Q R S T U V X Z

The Maestro had even worse torment in store for him. “Now, write B under A and the rest of the alphabet until you reach Z again, and complete the row with an A.”

I was already flipping through Giovan Batista Belaso’s La cifra del Sig to find the illustration.

“You see where you are going?” the Maestro said. “The next row would begin with C, yes? You would end by listing all Caesar alphabets possible with an alphabet of twenty-three letters. If you were to include some of the barbaric runes that northern tribes like the English and Germans use, you would have more.”

Vasco nodded uncertainly.

“Alfeo told you how easy it is to break a Caesar cipher. But if you use several Caesars by turn, then the cipher becomes unbreakable! Or so the sagacious Belaso believed and later authorities have agreed. The only thing you need to establish in advance with your correspondent is the order in which you will use the alphabets. No? Well, let us attempt an example. A little farther down the page write the sentence, ‘Sciara, who is furtive.’ In uppercase letters, if you please.”

Vasco wrote, SCIARA, CHE E CIRCOSPETTO.

“And then put it in five-letter groups, as Algol does.”