It cannot be doubted that earthen batteries, with guns in barbette, can, as a general rule, be more easily taken by assault, that they are more exposed to vertical and ricochet firing, and more expose their gunners to be picked off by sharpshooters.  Moreover, they give but a very limited fire upon the most desirable point, as the entrance to a harbor.  On the other hand, it has not been proved that masonry-casemated works, when properly constructed and properly armed, will not effectually resist a naval cannonade, whether from ships or floating-batteries.  The results of recent wars, and of the West Point experiments by General Totten, would seem to prove them abundantly capable of doing this.  Against such proofs the mere ad captandum assertion of their incapacity can have but little weight—­certainly not enough to justify the abandonment of a system approved by the best military authorities of this country and Europe, and sanctioned by long experience.

Major Barnard, in speaking of the capacity of masonry casemated forts to resist the fire of a hostile armament, and of the propriety of abandoning them for earthen batteries in our system of Coast Defences, uses the following forcible language:—­“When we bear in mind that the hostile ‘floating batteries,’ of whatever description, will themselves be exposed to the most formidable projectiles that can be thrown from shore batteries,—­that when they choose to come to ‘close quarters,’ to attempt to breach, their ‘embrasures’ present openings through which deluges of grape, canister, and musket balls can be poured upon the gunners; and consider what experience has so far shown, and reason has taught us, with regard to the casemate,—­we need not be under apprehension that our casemated works will be battered down; nor doubt that they will, as they did in Russia, answer the important purposes for which they were designed.”

“It only remains to show the necessity of such works.  It, in general, costs much less to place a gun behind an earthen parapet, than to build a masonry structure covered with bomb-proof arches, in which to mount it.  All authorities agree that an open barbette battery (Grivel’s very forcible admission has been quoted), on a low site, and to which vessels can approach within 300 or 400 yards, is utterly inadmissible.  It may safely be said, that in nine cases out of ten, the sites which furnish the efficient raking and cross fires upon the channels, are exactly of this character; and indeed it very often happens that there are no others.”

“When such sites are found, it rarely happens that they afford room for sufficient number of guns in open batteries.  Hence the necessity of putting them tier above tier, which involves, of course, the casemated structure.  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.”