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Show 3850 Gerdine- D 1871 of topography for the map, and if there are well- defined trails they are supposed to locate those trails with reference to the topography. Q Directing your attention to page 55, sheet T, I wish you would explain just what that reppesents. A That is a profile of the river, based on this survey; I mean the height of the river at the time the survey was made. As a man goes down the river he determines frequent elevations along the surface of the river, records those, and in connection with drawing up the plan we have been looking, at, they also make a profile, which is a vertical section of the river based on elevations established by the engineer at the time he traverses that section of the stream. Q From that profile are you able to determine what sections of the river are rapids? A Oh, yes. Q In what way? A By the slope. Q In topography is a certain slope within a certain distance -- is that recognized as producing a rapid? A Rapids are at various slopes; you understand, you could get a rapid with a fall of five feet in one hundred yard, and you would get a steeper and swifter rapid with ten feet in one hundred yards. Depends on the slope of the stream, in a sense, whether |