Millitary History of Obscurants Smoke Screens

Early History
The concept of millitary smoke screening dates back hundreds of
years. One of the earliest documented uses of smoke screen in
combat was the burning of green vegitation by the romans and
later the burning of peat moss by the Vikings. In the American Civil
War, General Robert Schenck burned wet tree limbs and leaves to
create a smoke screen to cover his retreat. In all of these early
smoke screen attempts, the method employed was direct flame
contact with combustible material.

These cumbustion methods were a bit uncontrollable and had only
limited advantages in combat. Generally, they could only be used
to conceal troop numbers or to cover a retreat but could not
effectively be used in covering troop advances due to the effect of
smoke on the advancing troops. In addition, because smoke is
lighter than air, the smoke cover was only temporary and large
volumes of smoke were necessary to create sufficient cover. Thus
a sizable amount of time was required to ignite and burn the
material.

WW I
During WW I there were two important improvements to the early
direct flame methods. One method was the smudge pot which
involved the burning of oil by contact with a heated metal plate thus
avoiding direct flame contact. This method had numerous
advantages over the direct flame methods in that it was more
controlable--being a uniform liquid in a specially designed
container--and it produced a much thicker smoke than did the
burning of peat moss or wood. However its product was still a
smoke and thus the smudge pot retains the three disadvantages
the direct flame methods: lighter than air, harmful to friendly
troops, and taking a fair amount of time to produce. In addition,
large amounts of oil were required to make the amount of smoke
necessary to cover large troop numbers and thus this method was
expensive and involved transport problems.

During the end of WWI, military researchers experimented with
naval uses for this method of smoke generation, and developed
apparatuses to fit a much larger equivalent of the smudge pot to
the engines of large naval ships. These inventions used heavy oil
pumped directly into the engines combustion chambers and
created huge columns of thick, black and toxic smoke that poured
out of the ship's smoke stacks. Once again, there many problems.
Hundreds of gallons of heavy oil were necessary to create a wall of
smoke less than a mile long, and the smoke cloud that was
created was lighter than air and disipated rapidly. Because of this
fact, many ships would be required to make sufficient cover for a
fleet. This type of smoke production saw very limited use in the
naval battles of WWI.

Another method that evolved at this time was the chemical smoke
bombs. This method produced by the mixing of chemical
compounds. The "smoke" produced was therefore not a smoke at
all--not being the product of combustion--but was instead a
chemical gas. The advantages of this method was that the gas
was highly controlable, could be produced in small containers (gas
grenades), and could be made heavier than air and thus linger on
the ground. Also, some of these gasses especially due to their
heavier than air properties could form a thicker screen than the
combustion methods. There were several disadvantages to this
system, however. First, the chemicals used were generaly highly
toxic phosphorous compounds, so, like the actual smoke of the
other smoke screen methods, this gas was neither useful to
advancing troops nor naval vessels. Secondly, the gas could not
be produced in mass quantities due to the expense of chemicals
involved and was thus generally only usable in small strike
operations.

Post WW I to Pre WWII
Sometime shortly after WWI, during the prohibition days, a rum
runner, and WWI veteran, named Alonzo Patterson developed an
entirely new method superior to all previous ones, but it remained
unknown to the millitary until the years just prior to the US
involvement in WWII. His invention was to become the first effective
large area smoke screen in the history of warfare, and every
millitary smoke screen technology from WWII to the present day
would be firmly based on his revolutionary methods. WWII. Before
the milliltary's discovery of the Patterson methods, early WWII
inventions were mere improvements on the smudge pot systems
and the chemical smoke screen methods.

Near the end of WWI to the beginning of WWII, leaders of the
worlds armies employed their greatest minds in to develop new
and better methods of making smoke. In fact, the United Staes
employed Thomas Edison as head of the U.S. Navy consulting
Board during WWI to, among other things, create an effective
smoke machine. Later, the Office of Scientific Research and
Deveolopment (OSRD) was formed, and one of its first projects
was to discover an effective large area smoke screen.

The early research of these organization was on technologies
based on the smudge pot and the chemical smoke bomb
methods. Numerous improvements were made but even at the the
start of WWII, they had not been able to discover an effective large
area smoke screen. At one point, the OSRD had almost given up
on smoke technologies after numerous experiments with oil and
chemical generators in Panama. But when the Patterson system
was brought to their attention, their interest in smoke screening
was quickly rekindled.

Early WW II -- The Patterson System
Alonzo Patterson was, during the prohibition days, a well known
and highly successful rum runner given the name "Smoky" by the
agents who attempted to chase his fleet of ships while being foiled
by his smoke screen. Near the end of Prohibition, Patterson
became a Customs Agent and gained several contacts in the
government. When US involvement WWII seemed imminent,
Patterson's contacts in the government, being highly aware of the
effectiveness of his smoke screen, asked him to refine his
technology for millitary use.

To this end, Patterson employed the help of his chemist friend
Harold Levy (the chemist who also invented Cellophane, among
other significant chemical inventions), to perfect the chemical
formulae already developed by Patterson years ago while
Patterson worked on refining the apparatuses necessary to the
smoke production system. Within a matter of months, the two had
refined the smoke screen system used by Patterson during his
rum running days, and the invention was presented to the
government during several demonstrations, some of which were
accomplished with the help of Andrew Higgins, a close friend and
business associate of Patterson who, during prohibition, had built
Patterson's rum running fleet according to Patterson's unique
designs.

In the end, the Navy and the other branches of the millitary, found
the smoke screen to be highly effective and extremely important to
combat. Prior to the Patterson system, millitary smoke screening
was, at best, a minimal factor in combat, but with the Patterson
system, millitary strategy was forever changed by the numerous
offensive and defensive advantages created by the first ever
effective large area smoke screen.