Page 84 - J. C. Turner "History and Science of Knots"

74 History and Science of Knots

direction. In 1923 he published a book with a detailed description of several
quipus.
The Swedish ethnographer Erland Nordenskiold was the first who tried to
interpret the content of the quipus. In 1925, shortly after Locke had uncovered
the code, he published two booklets, `The Secret of the Peruvian Quipus' [11]
and `Calculations with Years and Months in the Peruvian Quipus' [12]. He
assumed that the numbers indicate days and that the quipus contain astronom-
ical numbers. Unfortunately, his analysis lacks structure, and his calculation
methods are rather far-fetched. A first evaluation of his calculations was made
as late as in 1967 by Cyrus Day [9], a professor of English literature at Kansas
University.
In 1931 Henry Wassen translated parts of Guaman Poma's letter into
English, and interpreted an object on one of the drawings as a calculation
device [13].
The analysis of the contents was taken up by an American couple, the
mathematician Marcia Ascher and the anthropologist Robert Ascher. They
stressed the structure of the quipu as a whole and deduced statements about
Incan mathematics from what they found. Due to them is a detailed uniform
description of 215 quipus from museums and private collections all over the
world [5], and a beautiful, well-understandable book about quipus and their
cultural and historical context, `Code of the quipu' [6].

The Inca Culture

The Inca culture existed from about A.D. 1400 to 1560 in a region that is
now Peru and parts of Ecuador, Bolivia, Chile and Argentina (see Fig. 2).
The landscape varied widely from the deserts on the Pacific coast to tropical
forests and mountanious areas up in the Andes . Its three to five million inhab-
itants formed a state under a king, the Sapa Inca, who reigned at the capital
Cuzco. They had a common language, Quechua, a common religion, an effec-
tive system of irrigation , an extended road system , a system of taxation and
storehouses where they stored the agricultural and finished products they had
gathered as taxes in order to distribute them again in times of need. Therefore
they needed an extended bureaucracy. Yet they did not have any writing in
the sense we use the word, that is a direct transcription of spoken language.
They kept their accounts by tying knots into cords using an elaborated sys-
tem of number representation. These knotted cords were called `quipus', the
Quechua word for `knot'.