54 



History of Hingham. 



can well understand how pot-holes may have been formed in lo- 

 calities remote from any water-courses of the present period by 

 rushing - torrents through crevasses in the great ice-sheet. 



The pot-holes to be mentioned, though not found within the limits 

 of Hingham, are too near its borders, and too interesting as phe- 

 nomena of the glacial period, not to be noticed here. They are 

 to be found in Little Harbor, Cohasset, on Cooper's Island, so- 

 called, which however is not an island in the sense of being a body 

 of land surrounded with water, but from its being a somewhat 

 elevated land surrounded partly by water and partly by low, marshy 

 ground. There is a border of rocky cliffs on the northern portion 

 of the east coast of this island which end at a beach that separates 

 them from other cliffs farther south ; and it is near the termi- 

 nation of those first-mentioned and quite close to the beach that 

 the pot-holes are found. Just before this termination there is a 

 partial separation of the rocky mass by an opening on the water 

 side, which, however, rapidly narrows inland but a few feet from, 

 the water. It is on the northern side of this opening, that is, on 

 the rock that slopes towards the south, and very near the water 

 at low tide, that two of the holes, or what remains of them, may be 

 readily seen when the tide is out. 



Of the lowest of these, and the best preserved of them, and which 

 is designated as No. 1 in Figure No. 4, there yet remains a pot- 

 hole in the rock which will 

 hold water to the depth of 1 

 foot 9 inches, having a well- 

 defined rim just at the sur- 

 face of the water. The di- 

 ameter of it at rim is 25^ 

 inches ; below the rim 30 

 inches. Above this rim the 

 whole southern side of what 

 once formed a portion of the 

 pot-hole is gone ; but on the 

 northern side there remains, 

 as a concavity in the rock, 

 what formed a part of it, 

 having well-worn marks up- 

 on the surface; and these 

 are plainly discernible for a 

 height of four feet. From 

 the rock sloping away rapid- 

 ly above, it is very probable 

 that even these traces, wheh 

 •I prove a depth of six feet, do 

 not give the whole of that of 

 the original vessel when it 

 was intact. Exterior to this pot-hole the tide sinks below the 

 level of its bottom, but at high tide all is covered. 







Figure No. 4. 



