GULLIVER. — SHORELLNE TOPOGRAPHY. 167 



subaerially carved topography would be partly under water. The in- 

 equality would be proportionate to the relief of the land still exposed, 

 the change from the more even offshore bottom of the former sea area 

 to the uneven floor of the submerged area being less abrupt the more 

 gradual the depression. 



Criteria of submarine form have been very loosely used by writers in 

 the past. In some cases the same facts have been used to prove diamet- 

 rically opposed theories. Compare the use of inequalities of the bottom 

 by Dr. Spencer and M. Bertrand, the one to prove subaerial denudation 

 in the West Indies at a former greater elevation, while the other con- 

 siders all such irregularities in the English channel as the result of 

 warping. * 



All along the Atlantic shore of the United States, from Maine to 

 North Carolina, submerged channels have been revealed by the detailed 

 soundings of the Coast Survey ; and on the Pacific shore Professor 

 Davidson has shown many channels which are not continuations of present 

 river systems. IVIany of these are however undoubtedly the result of 

 warping, and all have been more or less cloaked over with land waste, 

 so an example surely in an initial stage following uniform depression 

 cannot be given. An example, which comes as near as any known to 

 the writer to being still in a very youthful condition since depression, is 

 in the bay of Maine (C. S., 103, 104, 105, 106), where the soundings 

 indicate very marked submarine channels, wliich are continuous with 

 land valleys. A small portion of this area is sliown in Figure 1. 



(2) Irregular New Shoreline : Scandinavia. — The intersection of the 

 sea with the uneven land surface produces an irregular shoreline, pos- 

 sessing many drowned valleys or rias t and arms of the sea between 

 headlands and islands. The degree of irregularity depends upon the 

 strength and variety of relief of the submerged area and on the amount 

 of submergence. 



For any given area, it is probable that there is a certain medium 

 measure of submergence which will give a maximum irregularity of 

 shoreline. The slopes above and below the water level will be essen- 

 tially identical, inasmuch as the shoreline lies at a level independent of 

 the form of the land. , 



The excessive irregularity of a drowned shoreline is well illustrated 

 by the coast of Scandinavia. The coast of Maine (Figure 1) is less irreg- 

 ular, both on account of a less mature dissection before drowning and also 



* See references. t See p. 22a 



