ing objects drift southward toward the sea,
while the heavier material upon the bottom is borne northward toward the
city piers. While, upon the surface, the ebb exceeds the flood both in
velocity and duration, the motions of the lowest water-stratum are
subject to the reverse conditions: it therefore follows that _the
heavier deposits from the city drainage cannot be swept away through
this the main avenue to the sea_. This contrast of motion between the
upper and lower drifts was observed in greater or less degree throughout
the entire distance from the Bar to a point in the Hudson River off Fort
Washington. These results appear to us of the highest importance, since
they would seem to indicate that the scouring action of the currents
will not be sufficient to prevent the accumulation of certain classes of
deposits in the upper harbor--as the ashes from the steamers, and the
like.

The course of the land waters in their progress seaward was followed
nearly sixty miles beyond the Bar, where currents of considerable
velocity were still observed. At the station farthest seaward, where the
sounding is thirty fathoms, the observations at different depths
disclosed some very remarkable peculiarities. It was perceived that the
moving stratum was not always of the same depth; the whole body of the
sea moving steadily forward at one time, while at another no motion
could be detected below a superficial stream.

The land waters, to which allusion has been made, augment the ebb
current to such a degree, that a general eastwardly preponderance was
observed in the drift along the south shore of Long Island; and this
preponderance, increasing steadily from station to station at each
remove, was found, at a point twenty-five miles east of Fire Island
Light, to outlive the tidal currents and maintain itself as a constant
coastwise stream.

One very curious discovery was made with regard to this stream along
shore. It was ascertained that during easterly gales a portion of the
water, crowded up into the bight of the coast, escapes seaward by a
sub-current. Shells, carefully marked, were deposited in the sea during
fine weather, and, after an easterly gale, were picked up on the shore
of Fire Island, _four miles eastward_ of the place of deposit. There was
no evidence that these shells travelled any distance during still
weather.

We do not despair of the possibility of artificial improvements at the
Long Island inlets.

At pres