Page:The National Geographic Magazine Vol 16 1905.djvu/92

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has been attained in the portrayal of the forms and characteristics of the strip of the sea bottom which borders the coast than is yielded by measurements ob- tained by dropping a sounding-plummet at close intervals, and that nearly all coasts and harbors, whatever may be the initial completeness of the surveys, re- quire reexamination in the course of time to disclose the altered conditions that are produced by natural agencies and artificial developments.

It will not escape attention that while there is a comparatively small total extent of completely surveyed coast which bounds the world's seats of enlightenment and wealth in the Northern Hemisphere, the extent of coast that is unex-