On this page, you'll find some features common to almost all
forts of the Second and Third Systems. The best way to find out
about this stuff is to take Ranger or docent guided tours of
them. They really know their forts and will bring out details
you'll never see on a self-guided tour.
These plain looking pictures show one of the more
interesting and least known features of fort building -
brick patterns. Specifically, look at the rows of long and
The photo on the left is a Queen pattern. The
rows alternate short-long. The short bricks are
whole bricks placed in lengthwise. This is the
strongest pattern in building and was used for weight
bearing walls and arches. It takes a lot of bricks,
On the right is the King pattern - long, long, long,
short. It's not as strong but uses much fewer bricks. It
was used for standard construction and floors. You'll see
both of these basic patterns throughout all brick forts,
including several variations of the King pattern.
These two photos are
examples of casemates. Casemates are covered areas
protected by heavy brick or stone construction from both
direct and indirect fire. "Casemated construction" , with
its many angles and arches, was the cornerstone of all
forts of the era. The arch is the most basic part of
casemate design. Arches can support much more weight than
a flat overhead because they distribute weight across the
whole arch and down the sides. Flat overheads bears all
the weight within their own area. Arches can also
absorb more damage and still maintain structural
The casemate on the left is a
passageway to allow soldiers to move about the fort during
The casemate on the right is a firing
casemate. Both cannon and rifles could be fired through
firing apertures around the left of the arch. (An example
is shown below in the Guns section.)
Large heavy wooden doors with rifle slots could close off
these casemates into independent fighting positions if the
enemy broke through. The large casemates on the right were
also used as storage, guardhouses, sleeping areas,
kitchens and prison cells.
Here are two more
examples of casemates. These are both from Fort
Pickens but will be seen at all system forts.
On the left are the large firing casemates seen from the
inside of the fort looking outward. You can clearly
see the firing apertures and the arches. The doors
are long gone, removed for safety reasons. Above the
casemates is the parapet with a cannon mounted on it.
This particular cannon is a 10 inch Rodman smooth bore
weighing almost eight tons. There were a dozen of
them lined up on this parapet, giving you an idea of the
strength of the construction. They were fixed in
position, held in place by steel pins. They could traverse
left and right with steel wheels on rails, giving them a
field of fire of almost 180 degrees.
right is a cross section of a casemate, courtesy of an
exploding powder magazine in 1899. This is the same
casemate as the photo on the left and is just off the
right hand side of that photo. Note the thickness of
the walls and the layer upon layer of bricks. Fort Pickens
consumed over 21 million of them. You can also see the
parapet. The 10 inch Rodman is further down the
Details and Craftsmanship
This photo contains a feature that blew me away and
would be totally missed unless it was pointed out to you.
Brick forts look very solid and connected - right? Wrong!
In this arched
passageway, you can see a thin black line going down the center
of the picture. That is a space between the interior of
the fort and
the outer wall. Turns out, they aren't
connected at all. The wall is built first, then the interior
is constructed inside of it.
There are two reasons for this. It allows the masonry to flex in
response to heat, cold and humidity. Without that flexing,
a rigid, solid brick fort would tear itself apart. It also helps limit
battle damage. If a wall or an arch collapses, it won't
cause everything else attached to it to cave in.
Look for these spacers in all forts. They aren't cracks
caused by age or shifting. They are built in by design.
This photo shows the entrance to a
powder magazine, the most vulnerable area of the fort.
Most forts cannot survive the explosion of a powder
magazine, so builders went to great lengths to eliminate
in house hazards like sparking and sabotage. The floors,
walls and ceilings are made of wood, fastened with wooden
pegs instead of nails. The door is wood also. All bars,
hinges and locks are made of brass, which doesn't spark. Inside,
everything is wood. Men working inside didn't wear boots.
The door was kept locked and stores handed out through the
opening on top of the door. Since they were deep inside the fort,
lighting was a challenge. The solution? Candle lanterns.
Made of brass. Lit outside the room and very carefully
The craftsmanship in these forts is unbelievable. You see
it everywhere but here are a couple of examples. All
of these edge bricks forming the archways had to be hand
cut and fitted. Even the smaller forts like Gaines and
Barrancas required millions of bricks. Large ones like
Pickens and Morgan used tens of millions. Arches,
doorways, turns, stairwells, firing apertures, vents and
other components required special attention like that seen
here. The number of custom bricks had to be in the tens of
thousands. Many of these forts have survived storms,
floods, erosion, climate extremes and other hazards for
well over a century. In some cases, the original
cement has fallen away. Yet the forts stand solidly
because of the quality of masonry that went into them.
It may not
look like it but you are approaching a brick fort,
bristling with guns and men, from the land side.
This is called the "glacis." It is a dirt slope
built up against the outermost wall to shield it
from direct fire and observation. You can also get
the same effect by digging the fort into the ground,
instead of on top of it. The disadvantage of a
glacis is that it prevents the use of layered cannon
to defend from land attack. Some of the glacis of
these forts is so good you can't even tell you're
walking up on something until you're right on top of
it. This one, at Fort Barrancas, is pretty good at
that. You won't see any glacis on the seaward side
of a fort. The multiple layers of cannon are
necessary to engage their main target - enemy ships.
Attacking ships will have a clear view of the
seaward side of the fort.
over the top of the glacis, this is what you would
be confronted with. Awaiting you is a long steep
drop into a dry moat taking rifle and cannon fire
from three sides. The steep drop down into the
moat is called the "counterscarp." The wall of the
fort is called the "scarp." On top of that is
the "parapet." Note the firing apertures along
the scarp. These would have shielded smaller, faster
firing cannon, probably 12 pounders, spitting out
canister and grapeshot as fast as they could.
There are also many rifle slots and there would have
been guns and men on the parapet too. Obviously,
this is not a good place to be attacking, which is
one of the reasons it never happened. There would
have been no escape. This dry moat is at Fort
Pickens and was six to eight feet deeper than it is
now. This enabled the cannon and rifles to
fire down into the moat instead of across at each
One of the weaknesses of
single wall linear forts is that the closer you get, the
less dangerous they become. As attackers rush the walls,
it becomes harder and harder for the defenders to fire
upon them. One of the ways Second and Third System forts
addressed that weakness was through the use of
bastions. These are reinforced blockhouses
that project out beyond the perimeter wall but are still
connected to the fort. (A similar defensive
structure not connected to the fort is called a redoubt.) This
allowed them to bring fire to bear right along their own
walls with cannon and rifle. The cannon would have been
smaller caliber firing canister or grapeshot, turning them
into giant shotguns.
The photo on the left is a
bastion at Fort Gaines, AL.
It had five of them - one on each corner of the
pentagon-shaped fort. The main batteries were mounted en
barbette on top of the bastions. It guarded the
western side of the entrance to Mobile Bay. Fort Gaines
was a fairly small fort, built with six million bricks. Its big
brother, Fort Morgan, can be seen through the lamp posts.
It's about three miles away and was built with 20 million
bricks. Mobile is about 20
miles to the left of the picture. Off the right side of
the picture is the Gulf of Mexico. The area between the
two forts was the main battle area of the Battle of Mobile
Bay on August 9, 1864.
The photo on the right is the
inside of this same bastion. The arch construction
here is very complex and extremely well preserved. You can
see firing apertures all around as well as a ventilation
opening. The circular insert in the middle is access
to a cistern that gathered rain water. Each bastion
had one. A spiral staircase goes up to the eight ton 10 inch
Rodman gun on top. Much of Fort Gaines was destroyed by
a two day bombardment from both land and ships after the
sea battle on August 9. With the walls breached and the
ammunition storage exposed, the fort surrendered on August
When they did, the Union called off its full
blown ground attack scheduled for the next day. Then it
was on to Fort Morgan, which held on for two more weeks.
This is parapet
mounting of heavy cannon. In the language of fort building,
firing over a parapet is called "en barbette." There are a
couple of features common to forts of the era. The gun is
mounted on granite, which won't crack or get grooves in it
like brick. It has steel wheels on steel rails for movement.
Men using jacking bars can lever the gun around pretty
quickly, even though this particular gun - a 15 inch Rodman
- weighs 40,000 pounds. The carriage stays in place and the
gun recoils to the back of it. This type of mounting gives
the gun a 360 degree firing fan but offers scant protection
for the crew. Also, it is a muzzle loader and the muzzle is
higher than a man. This presents obvious difficulties,
especially when trying to reload under fire.
This is a casemate
mounted muzzle loading cannon. It is also on a fixed
carriage with steel wheels. The wheels run along a
semi-circular track made of granite. Some mounts like
this will have rails on the granite. The gun recoiled along
its own carriage which put it into position to be reloaded.
Then it was cranked back into position for firing.
Even though it provides crew protection from enemy fire, it
has hazards of its own. One can only imagine the
concussion and backblast produced in this confined space
when the gun fired. If the blast doors were closed and
the casemate sealed up, it would be unbearable.
Here is another
little feature built into the casemates. The photo is
actually looking up at the ceiling over a casemated gun.
That is a ventilation shaft. In theory, smoke would go
out and fresh air would come in. No word on how those
The business end
of a casemate mounted cannon. This level is about head
height on a man. A gun here would have been used for
close in defense and/or to fire at ships within range. The
angled aperture gives the gun a bit of a range fan but not
much. The muzzle would need to be extended more through the
aperture so the blast
would be directed outward. If the gun wasn't completely
clear and/or nicked the brickwork when fired, it would be bad
news for the crew.
I hope you've enjoyed this little pic-tour-ial and will get out
and do some exploring.