SALT MARSHES -PAST AND FUTUREf 



thing of an animal and vegetable nature has 

 come in since then, including the salt marshes 

 themselves, which are made up of various 

 growing grasses on top, and, in their entire 

 thickness of closely woven sod and thick black 

 soil, they are largely of vegetable origin. One 

 must picture this region at the close of the 

 glacial period, therefore, as entirely destitute 

 of the most striking feature of to-day, a region 

 of brown land and blue water, but lacking the 

 great blanket of green marsh. 



As one looks inland from the Ipswich dunes 

 over the broad plain of salt marshes, the 

 rounded form of Hog Island— the birthplace 

 of Rufus Choate— looms up as a conspicuous 

 object in the landscape. It is a typical drum- 

 lin, one whose duplicates are to be found 

 everywhere in northern Europe and America, 

 where the ice sheet of the last glacial period 

 formerly held sway. It is a smoothly rounded 

 accumulation of turf-covered gravel a hun- 

 dred and forty feet high, somewhat steeper 

 on the north than on the south side, but as 

 featureless as an inverted punch-bowl. On 

 the western side its curves are cut by the flat 

 plane of the salt marsh. Scattered here and 

 there in the marsh are to be seen lower 



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