Khipu with summary cords

This exceptionally large but incomplete khipu consists of 438 cords whose arrangement and knot values are consistent with the Inka decimal accounting system, base 10. With two exceptions, its pendants form groups of 10 + 1 = 11 cords, forming a total of 39 cord groupings, in which one cord of the group is a “summary cord,” which points up from the main cord. While it appears to be a single khipu, it is, in fact, composed of two khipus spliced together. Although the 10 + 1 arrangement of cords is identical between the two khipus, there are more subsidiaries on the smaller khipu to the left, and the larger khipu not only has more colors, including blue, but it has several cords where knots were clearly untied.

This photo both shows the khipu’s remarkable structure and gives us a glimpse into the collector’s analytical thought process. In order to study the structure of the khipu, Conklin mounted the main cord horizontally with pendant cords hanging straight down and summary cords pinned up. Subsidiaries of both pendants and summary cords are mounted at angles, highlighting their greater concentration in the smaller khipu on the left.