1. INTRODUCTION
This section is based on various types of Japanese
documents, obtained from several sources. They have
been arranged according to subject matter as far as
possible. Some are given almost verbatim, while others
have been edited to eliminate repetition and parts considered
of little or no value. The individual documents
are separated by the use of dashes.
2. MOVEMENT IN JUNGLE COUNTRY
a. During the Day
Although it is said that the jungle is ideal for the individual
soldier, if he does not carry woodcutter's equipment he will often
find it impossible to get through. Although the density of jungle
varies, a woodcutting group of 20 to 30 men under the direction
of an officer is necessary for a single column (one team under the
man in charge of blazing the way, and several teams under the
man in charge of cutting through).
Speed in passing through jungle will depend upon its density, but
in general 1 kilometer (5/8 mile) will require 2 hours.
To maintain direction, a compass should be used; even so, mistakes
in direction are sometimes made because of the tendency to
keep following the easiest terrain. Moreover, the magnetic declination
on Guadalcanal Island must not be forgotten; that is, to advance
west by compass, one must advance
approximately 7°40' northwest. Therefore, it is important to search out the highest
ground possible and orient one's self before proceeding.
For bivouacking in a jungle, the foot of a slope is best because
it has cover from bombing or strafing. The area around streams
might easily be a target for enemy planes, and so is not suitable.
Use such things as small whistles to keep contact in the jungle,
but do not shout carelessly, especially at night. On high ground
in the jungle, the enemy has installed microphones to learn of our
approach and make it possible to bombard us. Often it is impossible
to get artillery pieces through the jungle unless they are
dismantled.
In the jungle the Americans build individual shelters, surrounded
by wire entanglements, or concealed; and, when we approach,
they fire tracer bullets or signaling shots to direct bombardment.
In grass plots in the jungle, the enemy sometimes prepares a
concentration of fire. It is especially important to search in advance
the border areas between jungle and grass plots.
The enemy is extremely well equipped with artillery and heavy
infantry weapons, and, on seeing us advance, they freely open
up with heavy fire. Therefore, in advancing through open country
by day, it is important to cooperate well with our own
artillery.
When the enemy discovers even an individual soldier, whether
by day or night, they bring concentrated fire on him. Make use
of this by causing the enemy to waste his bullets. That is, place
imitation targets where troops are not disposed, and at night
carry out such clever deceptions as lighting lamps.
In the jungle there are covered machine-gun emplacements at
unexpected points. If the first line of troops discovers them, they
must take measures to destroy them immediately.
The enemy has few tanks and they are slow, so they can easily
be destroyed by such weapons as our rapid-firing gun and infantry gun.
The enemy greatly fears our assaults. Do not forget that final
victory always lies in hand-to-hand battles.
b. At Night
Movement within the jungle at night, especially the movement
of large units, is extremely difficult. When passing through the
jungle at night, even when the course has been marked and plotted
during the day, contact is often lost, especially front to rear.
Therefore, it is essential to devise means of maintaining contact,
such as the use of punk (made from coconut husks), fireflies, and
phosphorescent substance (from decayed trees).
As the organization of fire by the enemy is precise, even at
night, care must be taken to deploy to such an extent that the
control of command will not be impaired. It is important to keep
from giving the enemy an opportunity to fire, by making use of
terrain features, camouflage, and crawling, and at the same time
to devote one's efforts to continuing the advance.
The foremost prerequisite of success is that each unit reach the
objective of its attack, and maintain the prescribed direction of
advance. It is extremely important to avoid mixing the units of
a force, and to keep friendly troops from attacking each other.
Therefore, conspicuous landmarks in the jungle area, especially
within and in front of the enemy positions, should be previously
designated, and it is essential to make the utmost effort to maintain
direction by use of the compass, by orientation from high
ground, and by every other method.
3. ASSAULTING ENEMY POSITIONS
The terrain within the enemy positions is generally flat, with
the exception of the Lunga River area, and traffic is unrestricted.
Therefore, within the positions, expect attacks from enemy tanks,
covered machine-gun positions, and, at times, concrete pillboxes
in the second- and third-line positions.
As a counter measure, prepare hand-to-hand fighting (demolition) squads
of infantry and engineer troops, and advance them
to the foremost lines. Do the utmost to inflict a surprise attack,
and bring up light and mobile guns (presumably light artillery)
near the first lines. If conditions permit, have the demolition
squads precede the first-line infantry to make the advance of the
infantry easier.
It is important to strengthen the shock troops, and to make
sure that these troops, by the use of terrain features and camouflage,
reach the flank and rear of the enemy firing point and attempt
a sudden penetration. At such times, the enemy attempts
to fire pistols and throw hand grenades at the nearest of our penetrating
troops; therefore it is necessary to penetrate by throwing
hand grenades in order to hold the initiative.
Upon occupying enemy positions, it is imperative to pursue the
fleeing enemy immediately. By halting, on the other hand, heavy
losses from enemy fire might easily be incurred.