Such works, furnishing from their lower tier a low, raking fire, and (if of several tiers) a plunging fire from their barbettes, offer as favorable emplacements for guns as can be contrived, and afford to their gunners a degree of security quite as great as _can_ be given to men thus engaged." "On subjects which have a mere speculative importance, there is no danger in giving rein to speculation; but on those of such real and intense practical importance as the security against hostile aggression of the great city and port of New York, it is not admissible to set aside the experience of the past, or the opinions of the best minds who have devoted themselves to such subjects.

A means of defence, sanctioned by its being confided in to protect the great ports of Europe--which _has_ protected the great ports of Russia against the most formidable naval armament that ever floated on the ocean, has a claim upon our confidence which mere criticism cannot diminish; and a claim to be adhered to in place of all new 'systems,' until time and trial shall have _necessitated_ (not merely justified) the change." "If, then, we refer to the practice of other nations, to find what has been judged necessary for the defence of important ports,--to experience, to find how such defensive systems have stood the test of actual trial,--we may draw useful conclusions with regard to what is now required to defend New York.

We shall find at _Sebastopol_--a narrow harbor, which owed its importance to its being the great naval depot of Russia on the Black Sea--an array of 700 guns, about 500 of which were placed in five 'masonry-casemated' works (several of them of great size), and the remainder in open batteries.

These defensive works fulfilled their object, and sustained the attack of the allied fleet, on the 17th of October, 1854, without sensible damage." "The facility with which seaports are attacked by fleets--the enormous preparations required--the great risks encountered in landing a besieging army on the coast of a formidable enemy (while, for protection against the _former_ species of attack, costly works are necessary, and against the latter, field works and men can, in emergency, afford protection), naturally caused the Russians to make these water defences their _first_ object.

Yet, though almost unprotected on the land side, Sebastopol resisted, for a whole year, an attack on that quarter; and illustrated how, with plenty of men and material, an energetic and effectual _land defence_ may be improvised, where the _sea defence_ is provided for, as thoroughly as it was at that place." "Let Cronstadt be another example.