This analysis is a specific study that investigates the role ethos plays in the scientific papers of American glacial geologists. Five articles, spanning the time period 1839–1988, a time period which saw the tentative beginnings, development, and maturation of glacial research and theory, were analyzed to determine the rhetorical strategies the writers used to establish their particular research and writing as being good science worthy of recognition and acceptance by their communities of glacial geologists. Early articles were written to portray the author's notion of good science as a strict attention to personal observation and analogy. Articles in the middle period continued to stress personal observation, but also appealed to the observations of other workers. The most contemporary articles favored quantified relationships and precise measurement.