The branches of the covert way of the west front bear well upon the channel above the fort, and are arranged to receive thirty-one guns.

To increase the fire down the and in passing, an external battery has been constructed communicating with the covert way of east front. The earthwork had been entirely completed, parapets formed, &c., but at the time it went into rebel possession it is believed that neither the breast-neither the breast-height walls were built nor the gun platforms laid. (This work has probably been done since.) It had capacity to receive twenty-five guns. It is quite likely that the rebels have armed this battery.

The work is arranged therefore for armament as follows:

Casemate guns............................................... 16

Barbette on two channel-bearing faces of main work........... 22

Barbette on two extremities of glacis-coupe, having the same bearing on the two faces.................................... 17

Barbette covert way of west front (looking up the channel).. 31

Barbette exterior battery................................... 25

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Total channel-bearing guns..................................111

Add barbette guns on other fronts........................... 16 ----

Total heavy guns...........................................127

(The ten flanking 24-pounder howitzers are not included in this summary.)

At the time the work went into the possession of the rebels there were in it, of guns, sixteen 32-pounder guns, twenty-six 24-pounder guns, ten 24-pounder flanking howitzers; of carriages, fourteenth 24-pounder casemate carriages, nine 24-pounder flank-defense howitzer carriages, twelve 24-pounder barbetter carriages.

It is supposed the above carriages were in a very bad condition. The sixteen 32-pounders were sent there to go into the casemates, in which 24-pounder had been mounted twenty years ago.

The report that the work had sunk so that the casemate guns would not fire over the levees is one of those canards which had its flight long ago; is a specimen of what reports malice or credulity will originate or entertain; and is quite on a par with some which have been sanctioned by high authority, that certain forts would fall down by the discharge of their artillery.

When I took charge of this work in 1840 the report was that the whole work had disappeared. It had settled probably about a foot. At that time the soles of the embrasures were, say, 6 feet above low water of river and 1 foot above high water. The levee in front (higher than necessary) was, say, 1 foot 2 inches higher than the sole of the embrasure (about on a level with the muzzle of the gun).

I cut out the embrasures and raised them 1 foot. The work has settled very little, if at all, since then.

The muzzle, or rather the axis of a casemate gun, should therefore be 1 foot higher than the top of the levee, and by cutting away 1 foot of the levee (which may be safely done at all times) there would be 2 feet difference of leave.

The river rises and falls feet, the surface being 7 feet and 2 inches below the top of the levee at low and high water.

Occasionally the river falls 1 foot lower than ordinary low water and rises 6 inches higher than ordinary high water, or has an extreme fluctuation of 6 feet 6 inches.

The glasis-coupe is surrounded by a wide wet ditch. This ditch has but little over 3 feet in it at low (ditch) water, and its bottom is firm