Soon 
certuries later these ice blocks,melted sway, the protect er 
of gravel and sand collapsed into the holes wi } 
and the unconsolidated material barked egsi 
gradually slumped toward the bottoms of the 
action which produces long and narrow or 
wind action which makes a broad shallow tlowout, nor fr 
which subdues and fills deep holes is a satisfactory; explanation for 
pits with such shapé and ‘distribution. Furthernere, several of SEEM, 
such as those occupied by Long Pond and Cyster Fond near } 
or one lying southeast of Signal Hill in Sa ardvich,excernd fon yithnin 
the plain to within the bordering superficial glsci 
‘these hollows ‘interrupt the continuous frort o 
‘must have formed -after the moraine was ruilt on top of the mar 
of the outwash plain by readvancing ice. Clearly then these ‘are 
holes resulting from the melting of ice which had been bu a. 
the deposition of the plains 
One) 
Source of the Materials ac he: 
a) 
Two other conditions point to the fac 
of glacial outwash. The head of the plein 
more than 200 feet, which is far above any 
the recent past. River deposits at this 
a stream et this high levele Secondly, 
types known to oe out as solid. ledges rary 
plain. Pebbles of Sa tillite were 
and ina pit west of Coonamessett River, x 
44 
Carboniferous conglomerate .pebbles from the 
Basins were found at a dozen or more exposure 
ee those of the Boston region may 
calities The scarcity of these bs pas 
few piece that travelled 25-to 60 mile 
came mixed with far more abundant Bhone ss 
eties of rock like the Dedham ae whi 
part of every pebble count, probably came 
rock only a few miles away, although xo 
within 10 miles of the plain. i meee 
have travelled, the only plausible. soure 
are north ot west of Cape Cod. Southard 
by moving ite and its associated meltwater 
ence in the deposits described heree 
Marginal Area 
As already stated, the Buzzar 
are telts of glecial ia Reoate 
were leid on top of stream-weshed 
the pitted pla 
northern margins of 
like the-gravel of he. 
all respects 
