 A map drawn by one of Alarcón's pilots is the earliest accurately detailed representation of the Gulf of California and the lower course of the Colorado River.Alarcón is almost unique among 16th-century "conquistadores" in that he reportedly treated the Indians he met humanely, as opposed to the often reckless and cruel behavior known from accounts of his contemporaries.Bernard de Voto, in his 1953 "Westward the Course of Empire", observed