A discovery made in a remote mountain village high in the Peruvian Andes suggests that the ancient Inca used accounting devices made of knotted, colored strings for more than accounting.

The devices, called khipus (pronounced kee-poos), used combinations of knots to represent numbers and were used to inventory stores of corn, beans, and other provisions. Spanish accounts from colonial times claim that Inca khipus also encoded history, biographies, and letters, but researchers have yet to decipher any non-numerical meaning in the cords and knots.

Now a pair of khipus protected by Andean elders since colonial times may offer fresh clues for understanding how more elaborate versions of the devices could have stored and relayed information.

“What we found is a series of complex