158 The American Geologist. September, ls&6 
frnin tlie coast, the relief is less distinet, but the contact-line 
is marked by the furrow occupied by a small brook which Js 
traceable westward, ptissing some GOO feet south of ]iaker sta- 
tion, to the low mound of gravelly till which forms the north- 
ern face of the deposit delimited on the map by the forty-foot 
contour line. .This latter portion of the front is a morainal 
phase; and two cuts, one where the railroad and the other 
where the carriage road cross the deposits, show boulders from 
three to five feet in diameter commingled with the gravell^^ 
till. The head or terrace itself does not rise more than 
ten feet above the fosse, and the back-slope is vei'y gentle. 
Without the strong evidence of ice-front conditions exhibited 
in the washed phase of the line near Gaspee point, it would be 
difHcuIt, perhaps, to maintain in New England the view here 
set forth. This plain, west of the railroad station, grades 
down rather steeply and is scattered over wefet of the carriage 
road with Carboniferous waste in fragments often exceeding 
six inches in diameter, all the evidence going to show the 
morainal nature of the deposit. The front comes down to the 
Spring Green pond fosse with traces of lobes. It is probable 
that this front has been somewhat modified by the drainage 
through this east-west depression, both that contemporaneous 
wuth the Passeonkquis stage and that whicli has taken place 
since. 
PAWTCXET STAGE. 
It is obvious from an inspection of a map of this region 
that the Pawtuxet river in running froju the crystalline up- 
lands west of Narragansett bay takes an indirect course to its 
debouchure. That this is not its preglacial course is also 
shown by the existence of rapids or falls at the point where 
it escapes into the sea at Pawtuxet. A diagnosis of the sand- 
plains, through which the course of this river is laid, shows 
that, like the Potowomut to the south, its path depends upon 
the occurrence of a well defined fosse at the head of a series 
of nearly s^nichronous sand-plains which are here denominated 
as the Pawtuxet stage of ice-retreat. The river follows this 
northeastward and backward course for about six miles, while 
its preglacial channel seems to have passed into Greenwich 
bay along the line of Gorton's pond and Apponaug river. 
(See dotted course on plate ^\.) 
