So What is Gunpowder?
Gunpowder, also called black powder, is a mixture of sulfur,
charcoal, and potassium nitrate. Gunpowder can be made just using
potassium nitrate and charcoal, but without the sulfur, the powder
is not as strong. It burns rapidly, producing a volume of hot gas
made up of carbonic acid and nitrogen, and a solid residue of
potassium sulfide. Because of its burning properties and the amount
of heat and gas volume that it generates, gunpowder has been widely
used as a propellant in firearms and as a pyrotechnic composition
in fireworks. The term gunpowder also refers broadly to any
propellant powder. Modern firearms do not use the traditional
gunpowder (black powder).
Gunpowder is classified as a low explosive because of its
relatively slow decomposition rate and consequently low brisance.
Low explosives deflagrate at subsonic speeds. High explosives
detonate, producing a supersonic wave. Ignition of the powder
packed behind a bullet must generate enough pressure to force it
from the muzzle at high speed, but not enough to rupture the gun
barrel. Gunpowder is thus less suitable for shattering rock or
fortifications, where high explosives such as TNT are
preferred.
Some History to it
During the American Civil War, Confederate military forces faced
shortages ofmany critical materials, but gunpowder was rarely among
them. Thanks to its abundance of saltpeter caves, the South built a
first-rate niter and gunpowder industry almost form the ground up.
Even at the end of the war, powder mills were still operating and a
supply of gunpowder was on hand. In the 1860s, the principal
ingredient of black gunpowder was potassium nitrate, derived from
niter or saltpeter as it was called. Each powder grain contained
about 75 per cent niter, together with charcoal (1.5 percent) and
sulfur (10 percent). When war began between North and South in
April 1861, the Confederacy did not possess an adequate supply of
gunpowder. Planned importation of powder could not meet all of the
South's needs, as the Union blockade of Confederate ports quickly
proved. Thus, the need for a strong, home-based gunpowder supply,
and consequently a steady source of niter, became evident. Among
the potential providers of niter were the numerous saltpeter caves
in the limestone regions of the Southeast. The Southeast abundance
of such caverns in the carbonate rock masses west of the Blue
Ridge. niter. Eventually, Virginia (along with parts of eastern
West Virginia) provided more of this strategic resource than any
other Confederate state (Schroeder-Lein, 1993a).
important mineral contribution to the Confederacy
Besides this most basic necessity for mid-nineteenth century
warfare, the Southeast provided massive amounts of lead, salt,
iron, and coal. For example, the lead and salt came exclusively h m
Austinville and Saltville respectively, iron mostly from
well-defined belts in the Valley and Ridge, and coal nearly
entirely from the Richmond coal fields.
GEOLOGY OF NITER DEPOSITS
The connection between caves and nitrate-rich deposits has been
known and exploited for centuries. For most of this time, organic
material (primarily bat guano) was assumed to be the source of cave
nitrates. Hess (1900) challenged this belief and asserted that the
saltpeter sediments of Mammoth Cave and other eastern caverns
formed through the activities of nitrify-producing cave in western
South. Caving bacteria in surface soils above the caves. There,
heems such as these produced massive amounts suggested, waters
percolating through the soils & dissolved of saltpeter for
Confederate military forces. The nitrate where water dripped from
cave roofs into floor sediments.
Although not entirely correct, Hess's basic idea of cave
saltpeter originating through the interaction of nitrate-rich
surface soils, groundwater, and nitrogen-fixing bacteria has drawn
strong support. Hill's (1981) work presents the most detailed
model, and is based on a comparative study of southeastern
saltpeter caves and western caverns rich in organic bat guano
deposits. Her study showed clearly that, although bat guano can
enrich cave earth in nitrate, it is not the only source and in the
southeastern caves not even a major source. Hill's model begins
with nitrifying bacteria in surface soils oxidizing organic
nitrogen to nitrate (NO -)which is then dissolved by percolating
groundwater and carried downward to anaerobic soils and rock where
it is reduced to ammonium (NH +). If caverns are present, the
infiltrating waters move toward the caves due to a moisture-density
gadient widm the bedrock created by evaporation at the cave
air-bedrock interface. Upon reaching the cave boundary, the
ammonium in solution is oxidized to nitrate with the help of
nitrifjmg bacteria. If porous cave sediment is in contact with the
bedrock, seeping groundwater will be drawn to the surface of the
sediment where evaporation and bacterial action cause nitrate
concentration.
About the area
These wheels used by the Confederacy to grind gunpowder at
Augusta, Ga in 1863-1864 were made in Woolwich, England and were
shipped on the blockade runner "Spray," via Mobile. After the war
Gen. Miles purchased them for use at Sycamore Powder Mills,
Cheatham County. They were exhibited at the Tennessee Centennial
Exposition in 1897.
Getting Credit for the Earthcache
Please answer the following questions, if you like to include a
picture of yourself in the log you may do so but you do not have to
if you do not one to
1.) How many grinding wheels are at the site and what color are
they and why are they that color?
2.) Who posted the historic marker here?
3.) In your own words how do you think they transported the
material from VA to TN during the civil war?
4.) What mineral deposits do you think are on these wheels
todays?
Please enjoy yourself at the Earthcache !!!!!!
