The language spoken by the Eora has, since the time of R. H. Mathews, been called Dharug, which generally refers to what is known as the inland variety, as opposed to the coastal form "Iyora" (or Eora). It was described as "extremely grateful to the ear, being in many instances expressive and sonorous", by David Collins. It became extinct after the first two generations, and has been partially reconstructed in some general outlines from the many notes made of it by the original colonists, in particular from the notebooks of William Dawes, who picked up the languages spoken by the Eora from his companion Patyegarang.