TOPOGRAPHY OF THE HARBOR ut 
mussels slows the movement of the water, the bottom may be built up an inch, 
or, locally, even several inches in a year. 
The only considerable areas of the harbor bottom below 1.5 feet which are 
at present covered by coarser materials are: the main channel of the Inlet, the 
deep hole at 1,400 north by 600 east, parts of the channel of the main fresh- 
water stream, and the bars on each side of the latter at 200 north and at 500 to 
600 east. ‘The main channel and deep hole have a bottom of gravel and bits of 
shell. The bars have a bottom often made up of alternate layers of mud and 
gravel. Because of the thinness of the gravel layers one often breaks through 
in attempting to walk over this part of the harbor bottom. These gravel layers 
are evidently spread over the constantly accumulating deposit of silt by the 
swifter current of the stream in times of flood. The bottom of the stream 
itself, from 0 to 580 south, is of gravel or small boulders in the shallow parts 
and of soft mud in the deeper holes. A small area with gravel bottom is found 
opposite the mouth of each small fresh-water rivulet along the shores of the 
harbor (indicated by FW on plate 1). These are but a foot or two in width, and 
often reach only half-way down the beach toward low-water mark. This is 
probably due to the fact that the bottom from the 2-foot level downward is so 
extremely flat that the water spreads out over it in very small, slowly moving 
rivulets (plate 118); that the masses of Ulva present turn the water or dam it, 
now at one point and now at another; and that such minute channels as are cut 
out of the mud during the short exposure of this low-lying bottom at low tide are 
filled in by wash of waves and by new deposits of silt when the tide rises. 
The boundary, or shore, of the harbor at the 8-foot level is in part natural, or 
undisturbed, and in part formed by artificial walls or wharves. The water-line 
of the natural shore at 8 feet is indicated on the map by a heavy solid line, 
usually more or less wavy, and marked frequently with a figure 8. The wharf- 
line is indicated by a similar heavy line, with short cross-lines added on one side. 
This line is generally more angular and straight, and not wavy. 
Beginning on the east side, we find the harbor bordered by vertical-walled 
stone wharves, practically all the way from the north end at 2,800 north, down 
to the old mill, at 500 north and 1,000 east. Along most of this distance, 1. e., 
from 2,200 north to the mill, as indicated on plate 1, the harbor bottom at the 
foot of the wall is at about the 1.5-foot level, while the wall extends up to a level 
of 8.5 or 9 feet (plate 111 B). South of the mill for 300 feet there is a sloping 
shore or beach between the 6 and 8 foot tide-levels, which is sparsely covered with 
gravel in some parts (plate 1vB). In other parts there is between these levels a 
sandy or peaty soil, of from 3 to 6 inches in depth, covered with Spartina patens, 
Juncus Gerardi, and other more thinly scattered species. From about 200 north 
to 100 south, the water’s edge, at high tide, les at the foot of the bank of a fresh- 
water canal. This bank is densely overgrown with shrubs and small trees. The 
level of the fresh water in the canal, during the five years of this investigation, 
was about 25 feet above mean low water. 
The 8-foot tide-line, from 160 south by 1,200 east, runs across a nearly flat 
eestuarial marsh, which for brevity we shall call the “ Marsh.” The line then 
runs west and northwest to 60 south by 1,000 east, then irregularly southwest, 
south, and westward to the road embankment at 575 south by 850 east. The 
western boundary of the harbor at the 8-foot level, from 625 south to 680 east, 
runs northward and northwestward, with a gravelly or narrow marshy shore, to 
