Rock- Hilh Lvii;/ fsland, X. Y. — Bri/.son. 231 
indenting the ridge in man}' places. The Manor branch of 
the Long Island railroad runs through one of these waterways, 
with only a slight gradient from north to south. Very little 
cutting or filling in had to be done along this part of the 
route. We find that most of the old roads crossing the island 
run through these natural depressions in the terminal moraine. 
It would never be suspected, perhaps, that this break in the 
ridge at Manor had anything to do in ff»rming the river chan- 
nel which is crossed by the south side railroad between Cen- 
ter and East Moriches; yet there is no doubt that a former 
connection existed. The writer has lately followed this de- 
pression up from the railroad to the ridge, and was surprised 
to find it uniting with other old channels that branch out from 
the Manor pass. 
Where these breaks occur in the ridge the morainic material 
is generally pushed farther southward, especially between the 
arms of the old watercourses. Thus we find Rock hill coming- 
down to within three miles of the bay, so that the boulder can 
be seen from the railroad at East))ort, if one knows where to 
look for it. 
To the right of the picture can be seen one of the okl river 
■channels that broke through the moraine at this point when 
the glacial streams prevailed. Staiuling on the ridge by the 
boulder, one can see the course of the natural depression cross- 
ing the frontal plain to the Little Setuck river where it enters 
the bay. North of the Manor branch of the railroad where it 
vinites with the main line, the channel is perfectly dry. South 
of it the water begins to percolate through the sand, and the 
8wamp and marsh lands of the south side begin. A noteworthy 
kame is here developed. and is referred to in "The Ups and 
Downs of Long Island," already mentioned. 
The main branch of the Setuck river is crossed by the rail- 
road a little farther east, and the original swamp lands, from 
which it had its rise, are covered with a beautiful sheet of 
water at Tuthill's mill. The old channel, however, oC which 
the chart of the U. S. ("oast Survey fails to give any pro])er 
idea, has been followed up by the writer through a tangled 
mass of brush to a large basin-shaped depression known as 
"Terrell's Hole." The channel becomes perfectly dry aliout a 
mile north of the railroad, and so is the kettle-hole depression ; 
