The high tides raised by the storm aforesaid partially filled our works, washing down parapets and impeding our operations as well as destroying our approaches; yet a fourth parallel was soon established,1
barely 300 yards from Wagner
, and only 100 from a sheltering ridge in its front, from behind which Rebel sharp-shooters had seriously impeded our working parties and defied efforts to expel them by infantry, as they afterward did2
to dislodge them by mortar-firing.
But Gen. Terry
was now directed to take it with the bayonet, and did so: whereupon our fifth parallel was established behind it, only 240 yards from Wagner
Here, the dry part of the island is but 25 yards wide and barely two feet high: high tides sweeping across in rough weather to the marsh behind it. Henceforward, the ground was filled with torpedo mines; in spite of which, a rude trench had been pushed forward, by daybreak of the 27th, to within 100 yards of the fort.
Yet here the progress of the besiegers was checked.
The fire of Wagner
, concentring from its extended front on this narrow sand-spit at close range, was necessarily most effective; that of the James island
batteries was steadily increasing in volume and accuracy; to push the sap by day was death to all engaged in it; while a bright harvest-moon rendered it all but equally hazardous by night.
It became necessary to silence the fort utterly by an over-powering curved fire from siege and Coehorn
mortars, at the same time attempting to breach the bomb-proof by a fire of rifled guns at close range; thus expelling the garrison from its only available shelter.
To this end, all the light mortars were brought to the front, and placed in battery; the capacity of tie fifth parallel and advanced trenches for sharp-shooters was greatly enlarged and improved; the rifled guns in the left breaching batteries were trained upon the fort; and powerful calcium lights prepared to assist the operations of our cannoniers and sharp-shooters, while blinding those of the enemy.
The New Ironsides, Capt. Rowan
, also moved up and set to work, during the day-light, on the obstinate fortress.
All being ready, our batteries reopened3
in full chorus: the New Ironsides pouring in an eight-gun broadside of 11-inch shells against the parapet, whence they dropped nearly vertically, exploding within or over the fort; while calcium lights turned night into day, blinding the garrison, and rendering visible to the besiegers every thing connected with the fort.
This proved too much for the besieged, who were compelled to seek and abide in the shelter of their bomb-proof, leaving our sappers free to push forward their work until they were so close to the fort that the fire of the James island
batteries, which had become their chief annoyance, could only be rendered effective at the peril of friends and foes alike.
And now the sap was pushed with vigor, and in entire disregard of the enemy: the workers off duty mounting the parapets of their works to take a survey of the ground; until, a little after dark,4
the sap was pushed by the south face of the fort, leaving it on their left, crowning the crest of the counterscarp near the flank of the east or sea front, completely