"The survey of the river proper was begun July 25, and completed December 31, 1911. The valley survey began January 15, and was completed September 10, 1912. Mapping in 1913." 1 map on 13 sheets, photocopy. "Revisions made July 1931." Depths shown by soundings. Relief shown by contours and spot heights. Scale: Approximately 1:24,000; Dimensions: sheets 92 x 122 cm