10 
Besides Bound Brook and the Gulf, the principal submerged 
or drowned rock valleys of this district are Weir River Bay 
and Strait’s Pond, Little Harbor, and Cohasset Harbor. These 
fiords, as remarked, are all far advanced in the process of silting 
up to the present level of the sea. Even Cohasset Harbor is a 
harbor in little more than name, presenting with the ebb of the 
tide a broad level expanse of mud and sand of great but unde- 
termined thickness ; while the widely extended marshes on the 
east and south show how greatly the area as well as the depth 
of the harbor has been reduced. The barrier beach bordering 
and limiting the salt marshes on the north has nearly separated 
the outer harbor from the Cove; and the soundings оп the 
chart indicate that a similar bar is now forming across the mouth 
of the outer harbor, from the Glades westward. In more ex- 
posed situations, the sea has already closed by barrier beaches 
two eastern entrances to Cohasset Harbor, the main entrance to 
Little Harbor, the eastern end of Strait’s Pond, and connected 
all the drumlins of the Nantasket peninsula by beaches from 
fifty feet to nearly half a mile in width. The numerous rocks 
and islets fringing this part of the coast are not the result of 
marine erosion; but these, and also the ledges, sometimes of 
great extent, now isolated by the salt marshes of Nantasket 
and Cohasset, testify equally with the submerged valleys to the 
subsidence of the land. Continued subsidence would sub- 
merge these ledges and isolate others, leaving the general 
aspect of the coast unchanged. 
MAPS. 
This paper is accompanied by two maps ( Plates I and IL). The 
first, on a scale of 2400 feet to the inch, embraces the entire 
peninsula of Hull, the whole of Cohasset, a portion of Scituate 
and all but the southern end of Hingham, or, in other words, 
the entire area to be deseribed not only in this paper but also in 
the following paper on the geology of Hingham. Topographi— 
cally, it is based primarily upon the Coast Survey chart of 
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