Career
He published several papers on the epigraphy and astronomy of the pre-Columbian Maya civilization, and he is most noted for being the first to decipher the nature and meaning of the series of glyphs in the Maya writing system known as the "Supplementary Series", proving they referred to the position of a given day in the lunar cycle. By this time (the mid-1920s), although a few details relating to the functioning of the Maya calendar system and some astronomical notation had been worked out, the great majority of ancient Maya inscriptions and glyphs remained mysterious and undeciphered.
