Crater Lake National Park: Administrative History by Harlan D. Unrau and Stephen Mark, 1987
CHAPTER ONE: Discovery And Exploration Of Crater Lake: 1853-1885
E. SCIENTIFIC STUDIES COMMENCE: 1883
In 1883 John Wesley Powell, director of the U.S. Geological Survey, sent Professor J.S. Diller and Everett Hayden to the lake as the first Geological Survey party to study the caldera and its formation. Their investigation of lava flows and rock formations would form the basis for Diller’s later theory that the mountain top collapsed rather than being blown away. They studied the geological features of Wizard Island to which they journeyed on a log raft, improvised by tumbling “logs over the cliffs to the water’s edge,” and lashing “them together with ropes.”  The results of their studies were published in various scientific journals, thus providing increasing publicity for Crater Lake among the scientific community in the United States.