Dr. Jeffrey Quilter of the Peabody Museum at Harvard University relates the story about a piece of paper his archaeological team excavated in northern Peru in 2008 and the remarkable word list written on it. An unknown colonial Spaniard in the early Seventeenth Century, on the back of a letter, wrote down Spanish number words and numerals alongside the words for those numbers in an unknown native language. Now, four hundred years later, that number list is the only hard evidence we have for a language whose name still is not even known for sure.
Produced in 2010 by Peabody Museum of Archaeology and Ethnology
Copyright 2010 President and Fellows of Harvard College
History of Peru (Wikipedia)
New Discovery: Traces of a Lost Language (Peabody Museum)
Traces of a Lost Language and Number System Discovered on the North Coast of Peru (Abstract, American Anthropologist, Vol. 112, Issue 3, pp. 357-369, September 2010; Wiley Online Library)