suggested that the Voynich manuscript text could be some little-known natural language, written plaintext with an invented alphabet. He suggested Chinese in jest, but later comparison of word length statistics with Vietnamese and Chinese made him view that hypothesis seriously. In many language families of East and Central Asia, mainly Sino-Tibetan (Chinese, Tibetan, and Burmese), Austroasiatic (Vietnamese, Khmer, etc.) and possibly Tai (Thai, Lao, etc.), morphemes generally have only one syllable. Child (1976), a linguist of Indo-European languages for the U.S. National Security Agency, proposed that the manuscript was written in a "hitherto unknown North Germanic dialect". He identified in the manuscript a "skeletal syntax several elements of which are reminiscent of certain Germanic languages", while the content is expressed using "a great deal of obscurity". In February 2014, Professor Stephen Bax of the University of Bedfordshire made public his research into using "bottom up" methodology to understand the manuscript. His method involved looking for and translating proper nouns, in association with relevant illustrations, in the context of other languages of the same time period. A paper he posted online offers tentative translation of 14 characters and 10 words. He suggested the text is a treatise on nature written in a natural language, rather than a code. Tucker & Talbert (2014) published a paper claiming a positive identification of 37 plants, 6 animals, and one mineral referenced in the manuscript to plant drawings in the Libellus de Medicinalibus Indorum Herbis or Badianus manuscript, a fifteenth-century Aztec herbal. Together with the presence of atacamite in the paint, they argue that the plants were from colonial New Spain and the text represented Nahuatl, the language of the Aztecs. They date the manuscript to between 1521 (the date of the Spanish conquest of the Aztec Empire) and circa 1576. These dates contradict the earlier radiocarbon date of the vellum and other elements of the manuscript. However, they argued that the vellum could have been stored and used at a later date. The analysis has been criticized by other Voynich manuscript researchers, who argued that a skilled forger could construct plants that coincidentally have a passing resemblance to theretofore undiscovered existing plants. Nahuatl specialist Magnus Pharao Hansen has rejected their proposed readings as pure nonsense. Constructed language The peculiar internal structure of Voynich manuscript words led William F. Friedman to conjecture that the text could be a constructed language. In 1950, Friedman asked the