GULLIVER. — SHORELINE TOPOGRAPHY. 153 



Initial is here used as the technical term to define the form at the 

 beginning of any geographic cycle or epicycle. Any dynamic process 

 which produces a change in the relative position of land and sea may 

 interrupt a cycle at any stage of development, and introduce a new 

 cycle. Later stages and forms will be called sequential. These terms 

 are offered to avoid the misconception, on account of their vernacular 

 meaning, of the terms constructional and destructional, sometimes used 

 for the identical ideas. 



Previous Work on Shorelines. — Since the days of Strabo and Aristotle, 

 two of the greatest observers among early geographers, much has been 

 added to the science of geography. Passing over the work * of the car- 

 tographers, explorers, and speculative writers, mention must be made of 

 the great mass of facts collected by Ritter and Humboldt and of their 

 use by Guyot ; but the great outdoor observer, De la Beche, whose work 

 was the stock in trade of the next generation, first interpreted many of 

 the coastal forms. He in 1834,t and Dana more fully in 1849,$ recog- 

 nized land-carved forms under water, or drowned valleys, as proof of 

 depression of the land. Robert Chambers recognized raised beaches and 

 associated coastal forms, and showed that the Atlantic coastal plain indi- 

 cated elevation. § Lyell with his doctrine of uniformity, Ramsay with 

 the tlieory of marine denudation, the Geikies, LeConte, Darwin, and 

 many other geologists, have worked out the changes in form of coasts 

 here grouped under various sequential stages. 



Members of the United States Surveys, Bache, Mitchell, Gilbert, 

 Shaler, Whiting, Davidson, and others, have worked out many of the 

 details of coastal forms and their changes, and a large number of obser- 

 vations recorded upon maps and charts have been the basis of much of 

 the work in this paper. 



In 1879, Dr. Halm discussed the rising and sinking of coasts, but he 

 did not consider the ratios between activities nor take into account the 

 time since which a given movement took place. Weule, Cold, Keller, 

 and Sandler have also studied shorelines, but the fullest discussion of 

 coastal and shore forms has been made by von Richthofen and his pupil. 

 Dr. Philippson.il 



* See Lyell, Prin. Geol., 11th ed., 1872, 22, 57 ; Woodworth, Am. Geol, 1894, 

 XIV. 210. 



t Theoretical Geology, 192-194. 

 X Geology of the Wilkes Expedition, 1849, 677. 

 § Ancient Sea Margins, 221, 253, 270, 276, 299. 

 II See list of references for these and other papers. 



