“Battery Hearn consisted of one 12-inch Coastal Defense Gun mounted on a
Barbette carriage and had a range of 29,000 yards.
Construction of the battery (formerly named Smith No. 2) commenced in
1918 and was completed in 1921 at a cost of $148,105. This made the
battery the last large caliber seacoast artillery emplaced on
Corregidor, when continuing ordnance development of the fortress was
limited by the Washington Disarmament Treaty.
Built in the era prior to air-power, the large round light-colored
concrete apron surrounding the gun made it a perfect bulls-eyes for
Japanese observers on Bataan.
In 1937 Smith No. 2 was renamed in honor of Brigadier General Clint C.
Hearn who had commanded the Harbor Defenses of Manila and Subic Bays in
1917.
The 1,000 lb armor piercing shell or the 670 lb High Explosive shell
required a 270 lb bagged charge. Rate of fire was one round every 55
seconds, and the standard complement was one officer and 33 enlisted
men, of whom 4 were stationed in the well beneath the carriage.
On 6 May, 1942, the gun and carriage were disabled by the crew, but not
sufficiently to have the Japanese use American POW's place it back in
service by replacing the mounted gun with the spare and stripping
useable parts from Battery Smith to rebuild the carriage.
During the pre-invasion bombing of Corregidor in late January/early
February 1945, a 1000 lb bomb exploded on the apron beside the gun,
putting it permanently out of action”.
(Information from Corregidor.org)
____________________________________

Pre-war photo of Battery Hearn..

Battery
Hearn was the location of this 1942 Japanese Banzai photo.

By the end of the war it looked very different as bombardment had taken
a heavy toll.
The aerial reconnaissance photo shown below was taken
February 16th, 1945 when Battery Hearn was still in Japanese hands.
Two days after the photo was taken, a significant night
battle would occur in this area resulting in the awarding of the
Congressional Medal of Honor. Accounts of the action are contained in
the following articles:
THE NIGHT OF A THOUSAND HOURS
and
THE BEST WARRIOR I EVER KNEW

(312th BG photo via Pacific Wrecks courtesy of Tony F.)
To show you “Then and Now” views of the area, I have labelled
significant landmarks so please refer back to this photo when looking at
the rest of the report.

#1-
The 12-inch gun with the underground magazines etc in the distance.
Sometime post war the barrel was raised a bit.

#1-
The gun mounted on the concrete “bulls eye”.

#2-
The 1000 lb bomb crater that put the gun permanently out of action.

#3-
The underground part of Battery Hearn contains the Shell and Powder
Rooms, Plotting Room, Power Room, Comms area and a rear entrance. I am
not sure what two other rooms are for, perhaps offices of some sort.

#3-
A closer view of the main entrance.

#3-
Looking from the main entrance out towards the gun. We will go
underground a little later.

#4-
To the side of the road is a spare 12-inch barrel. This is the original
gun barrel as the Japanese had the American POWs swap barrels during
their work to get the gun back into service.

#4-
Another view of the spare 12-inch barrel.

#4-
GUN.12-IN M1895 NO.8
ORD DEPT USA
WATERVLIET ARSENAL 1898
118,630 LBS INSP. G.W.B.

#5-
This rectangular structure is located across the road today. Inside it
is a concrete tub (right side) and a concrete circular object resembling
a large toilet (left side). My guess is that this was the battery
latrine.

#5-
Opposite end of the structure. There is a drain hole outside at the
bottom of the wall.

#6-
Here you can see two dark narrow rectangles in the aerial photo. These
are tunnel entrances. One is quite narrow and has a lot of rebar
sticking out so I did not go inside it. This one probably goes out under
the gun. The other one can be entered easily and goes inside to the
Plotting Room.

#6-
This tunnel goes to the Plotting Room.

#7-
There is a concrete set of steps up to the Battery Control Station. They
are mostly covered in vegetation today but I cleared a few steps for a
photo.

#8-
The Battery Control Station was a small structure built on top of a
platform over an airshaft. At the rear are a set of steps up to the
platform. A rectangular piece of concrete with large metal bolts would
have held some sort of range or direction finding equipment. It is rare
to see such an exposed Control Station, not much is left of it.

#8-
Rear view showing the concrete steps.

#8 -
Damaged triangular pedestal.

#9-
Concrete cover over one of the air ventilation shafts. The air vents are
slanted.

#9-
Side view of this air vent.

#10-
End view of the largest air vent as you come up on top of the hill. This
vent is above the Power Room and still has metal diesel exhaust pipes
sticking out through the roof. A metal rung ladder down the vent also
allows for access to the room or an emergency escape up if necessary.

#10-
Side view of this air vent

#10-
Looking across the air vent you can see part of the diesel exhaust
pipes.

#10-
In the opposite direction you can see the metal ladder.

#10-
It is a long way down.

#11-
The final air vent in the aerial photo is a bit further on the other
side of a big crater.

#12-
In the aerial photo you see the road disappear behind the hillside.
Actually this was a trolley line that went into the rear entrance of
Battery Hearn for the transport of heavy shells etc. A short ways inside
this entrance, a bomb has collapsed the tunnel. At the point of impact,
sunlight can be seen coming down a hole from the crater up above. This
photo shows the rear entrance with the roof caved in.

#12-
Under the collapsed roof, you cannot go far before it is a dead end.

#12-
Up the hillside above the Rear Entrance is a crater from the bomb that
collapsed the tunnel under it. Here I am standing on the edge of the
crater and using some camera zoom to look at the broken tunnel roof.
Straight ahead is rebar and a hole down into the tunnel below.
OK, enough
fun out here. Let’s go underground.