ry.

As a matter of course, notice was immediately given to all foreign
vessels in port of the proposed blocking of the Narrows and the Main,
Swash and East Channels with torpedoes, and forty-eight hours' time was
accorded them wherein to take their departure. The European steamers
were the first to leave, each one towing from two to five
sailing-vessels. Later on, General Hancock impressed all the harbor tugs
into service; and, by their aid, before the specified period had
elapsed, not a single ship floating a foreign flag remained in New York
Harbor. A battalion of army engineers, under command of General Abbot,
and another of sailors, under Captain Selfridge, at once began
operations.

In the Narrows, torpedoes were moored at distances of one hundred feet
apart, and were connected with the shore by electric wires. At various
points along the beach shell-proof huts were constructed, to which these
wires led. In each hut was arranged a camera lucida, so that a picture
of the harbor, over a limited area, was thrown upon a whitened table. In
this way an observer could recognize the instant an enemy's vessel
arrived over a sunken mine, and could explode the latter by simply
touching a button which allowed the electric current to pass to the
torpedo. In the Harbor channels the torpedoes were so arranged as to be
exploded on contact of an enemy's vessel with a partially submerged
buoy.

The torpedo-stations on Staten and Coney Islands and the Jersey coast
were provided with movable fish-torpedoes of the Ericsson and Lay types,
intended to be sent out against a hostile vessel, and manoeuvred from
the shore. All the steam-tugs in the Harbor were moored in Gowanus bay,
and each tug was rigged with a long boom projecting from her bow, on
which a torpedo, containing some fifty pounds of dynamite, was carried.

With the tugs, and serving as flag-ship for the squadron, was the U.S.
torpedo-boat "Alarm," Lieutenant-Commander H.H. Gorringe.

The armament of the sea-coast batteries was not calculated to strike
terror into the soul of any nation owning a modern ironclad vessel. It
consisted mainly of old-fashioned smooth-bore guns, a system of
artillery which has been rejected by every European power as the weakest
and most inefficient. The greatest range attainable with the best of
these cannon was 8000 yards, or some four and one half miles. At one
quarter this range their shot would be utterly unable to penetrate even
moderat