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Monday, March 27, 2017

Thermography as Measurement of Radiative Atmospheric Warming?

From Wikipedia, the free encyclopedia

Thermogram of a traditional building in the background and a "passive house" in the foreground

Infrared thermography (IRT), thermal imaging, and thermal video are examples of infrared imaging science. Thermographic cameras usually detect radiation in the long-infrared range of the electromagnetic spectrum (roughly 9,000–14,000 nanometers or 9–14 µm) and produce images of that radiation, called thermograms. Since infrared radiation is emitted by all objects with a temperature above absolute zero according to the black body radiation law, thermography makes it possible to see one's environment with or without visible illumination. The amount of radiation emitted by an object increases with temperature; therefore, thermography allows one to see variations in temperature. When viewed through a thermal imaging camera, warm objects stand out well against cooler backgrounds; humans and other warm-blooded animals become easily visible against the environment, day or night. As a result, thermography is particularly useful to the military and other users of surveillance cameras.
Thermogram of a cat

Some physiological changes in human beings and other warm-blooded animals can also be monitored with thermal imaging during clinical diagnostics. Thermography is used in allergy detection and veterinary medicine. It is also used for breast screening, though primarily by alternative practitioners as it is considerably less accurate and specific than competing techniques. Government and airport personnel used thermography to detect suspected swine flu cases during the 2009 pandemic.[1]
Thermal imaging camera and screen. Thermal imaging can detect elevated body temperature, one of the signs of the virus H1N1 (Swine influenza).

Thermography has a long history, although its use has increased dramatically with the commercial and industrial applications of the past fifty years. Firefighters use thermography to see through smoke, to find persons, and to localize the base of a fire. Maintenance technicians use thermography to locate overheating joints and sections of power lines, which are a sign of impending failure. Building construction technicians can see thermal signatures that indicate heat leaks in faulty thermal insulation and can use the results to improve the efficiency of heating and air-conditioning units.

The appearance and operation of a modern thermographic camera is often similar to a camcorder. Often the live thermogram reveals temperature variations so clearly that a photograph is not necessary for analysis. A recording module is therefore not always built-in.

Non-specialized CCD and CMOS sensors have most of their spectral sensitivity in the visible light wavelength range. However, by utilizing the "trailing" area of their spectral sensitivity, namely the part of the infrared spectrum called near-infrared (NIR), and by using off-the-shelf CCTV camera it is possible under certain circumstances to obtain true thermal images of objects with temperatures at about 280 °C ( 536 °F ) and higher.[2]

Specialized thermal imaging cameras use focal plane arrays (FPAs) that respond to longer wavelengths (mid- and long-wavelength infrared). The most common types are InSb, InGaAs, HgCdTe and QWIP FPA. The newest technologies use low-cost, uncooled microbolometers as FPA sensors. Their resolution is considerably lower than that of optical cameras, mostly 160x120 or 320x240 pixels, up to 1024×768[3] for the most expensive models. Thermal imaging cameras are much more expensive than their visible-spectrum counterparts, and higher-end models are often export-restricted due to the military uses for this technology. Older bolometers or more sensitive models such as InSb require cryogenic cooling, usually by a miniature Stirling cycle refrigerator or liquid nitrogen.

Thermal energy

A comparison of a thermal image (top) and an ordinary photograph (bottom) shows that a trash bag is transparent but glass (the man's spectacles) is opaque in long-wavelength infrared.
This thermogram shows excessive heating on a terminal in an industrial electrical fuse block.

Thermal images, or thermograms, are actually visual displays of the amount of infrared energy emitted, transmitted, and reflected by an object. Because there are multiple sources of the infrared energy, it is difficult to get an accurate temperature of an object using this method. A thermal imaging camera is capable of performing algorithms to interpret that data and build an image. Although the image shows the viewer an approximation of the temperature at which the object is operating, the camera is actually using multiple sources of data based on the areas surrounding the object to determine that value rather than detecting the actual temperature.[4]

This phenomenon may become clearer upon consideration of the formula:
 
Incident Radiant Power = Emitted Radiant Power + Transmitted Radiant Power + Reflected Radiant Power;
where: Incident Radiant Power is the radiant power profile when viewed through a thermal imaging camera. Emitted Radiant Power is generally what is intended to be measured; Transmitted Radiant Power is the radiant power that passes through the subject from a remote thermal source, and; Reflected Radiant Power is the amount of radiant power that reflects off the surface of the object from a remote thermal source.

This phenomenon occurs everywhere, all the time. It is a process known as Radiant Heat Exchange, since Radiant Power × Time equals Radiant Energy. However, in the case of Infrared Thermography, the above equation is used to describe the radiant power within the spectral wavelength passband of the thermal imaging camera in use. The Radiant Heat exchange requirements described in the equation apply equally at every wavelength in the Electromagnetic Spectrum

If the object is radiating at a higher temperature than its surroundings, then power transfer will be taking place and power will be radiating from warm to cold following the principle stated in the Second Law of Thermodynamics. So if there is a cool area in the thermogram, that object will be absorbing the radiation emitted by the warm object.

The ability of objects to emit is called emissivity, to absorb radiation is called absorptivity. Under outdoor environments, convective cooling from wind may also need to be considered when trying to get an accurate temperature reading.

The thermal imaging camera would next employ a series of mathematical algorithms. Since the camera is only able to see the electromagnetic radiation that is impossible to detect with the human eye, it will build a picture in the viewer and record a visible picture, usually in a JPG format.

In order to perform the role of non-contact temperature recorder, the camera will change the temperature of the object being viewed with its emissivity setting.

Other algorithms can be used to affect the measurement, including the transmission ability of the transmitting medium (usually air) and the temperature of that transmitting medium. All these settings will affect the ultimate output for the temperature of the object being viewed.

This functionality makes the thermal imaging camera an excellent tool for the maintenance of electrical and mechanical systems in industry and commerce. By using the proper camera settings and by being careful when capturing the image, electrical systems can be scanned and problems can be found. Faults with steam traps in steam heating systems are easy to locate.

In the energy savings area, the thermal imaging camera can do more. Because it can see the effective radiation temperature of an object as well as what that object is radiating towards, it can help locate sources of thermal leaks and overheated regions as well.

Emissivity

Emissivity is a term that is often misunderstood and misused. It represents a material's ability to emit thermal radiation and is an optical property of matter.

Each material has a different emissivity, which may vary by temperature and infrared wavelength.[5] For example, clean metal surfaces have emissivity that decreases at longer wavelengths; many dielectric materials, such as quartz (SiO2), sapphire (Al2O3), calcium fluoride (CaF2), etc. have emissivity that increases at longer wavelength; simple oxides, such as Iron Oxide (Fe2O3) display relatively flat emissivity in the infrared spectrum.

A material's emissivity can range from a theoretical 0.00 (completely not-emitting) to an equally theoretical 1.00 (completely emitting). An example of a substance with low emissivity would be silver, with an emissivity coefficient of .02. An example of a substance with high emissivity would be asphalt, with an emissivity coefficient of .98.

A black body is a theoretical object with an emissivity of 1 that radiates thermal radiation characteristic of its contact temperature. That is, if the contact temperature of a thermally uniform black body radiator were 50 °C ( 122 °F ), the black body would emit thermal radiation characteristic of 50 °C ( 122 °F ).
Thermogram of a snake held by a human

An ordinary object emits less infrared radiation than a theoretical black body. The fraction of its actual emission to the theoretical emission (of the black body) is its emissivity (or emissivity coefficient).

In order to make a temperature measurement of an object using an infrared imager, it is necessary to estimate or determine the object's emissivity. For quick work, a thermographer may refer to an emissivity table for a given type of object, and enter that value into the imager. The imager would then calculate the object's contact temperature based on the value entered from the table and the object's emission of infrared radiation as detected by the imager.

In order to get a more accurate temperature measurement, a thermographer may apply a standard material of known, high emissivity to the surface of the object. The standard material might be as complex as industrial emissivity spray produced specifically for the purpose, or as simple as standard black insulation tape, with an emissivity of about 0.97. The object's known temperature can then be measured using the standard emissivity. If desired, the object's actual emissivity (on a part of the object that is not covered by the standard material) can then be determined by adjusting the imager's setting to the known temperature. There are situations, however, when such an emissivity test is not possible due to dangerous or inaccessible conditions. In these situations, the thermographer must rely on tables.

Difference between infrared film and thermography

IR film is sensitive to infrared (IR) radiation in the 250 °C to 500 °C ( 482 °F to 932 °F ) range, while the range of thermography is approximately −50 °C to over 2,000 °C ( -122 °F to over 3632 °F ). So, for an IR film to work thermographically, it must be over 250 °C ( 482 ° F ) or be reflecting infrared radiation from something that is at least that hot.

Night vision infrared devices image in the near-infrared, just beyond the visual spectrum, and can see emitted or reflected near-infrared in complete visual darkness. However, again, these are not usually used for thermography due to the high temperature requirements, but are instead used with active near-IR sources.

Starlight-type night vision devices generally only magnify ambient light.

Passive vs. active thermography

All objects above the absolute zero temperature (0 K) emit infrared radiation. Hence, an excellent way to measure thermal variations is to use an infrared vision device, usually a focal plane array (FPA) infrared camera capable of detecting radiation in the mid (3 to 5 μm) and long (7 to 14 μm) wave infrared bands, denoted as MWIR and LWIR, corresponding to two of the high transmittance infrared windows. Abnormal temperature profiles at the surface of an object are an indication of a potential problem.[6]

In passive thermography, the features of interest are naturally at a higher or lower temperature than the background. Passive thermography has many applications such as surveillance of people on a scene and medical diagnosis (specifically thermology).

Active thermography

In active thermography, an energy source is required to produce a thermal contrast between the feature of interest and the background. The active approach is necessary in many cases given that the inspected parts are usually in equilibrium with the surroundings.

Advantages of thermography

  • It shows a visual picture so temperatures over a large area can be compared[7][8][9]
  • It is capable of catching moving targets in real time[7][8][9]
  • It is able to find deteriorating, i.e., higher temperature components prior to their failure
  • It can be used to measure or observe in areas inaccessible or hazardous for other methods
  • It is a non-destructive test method
  • It can be used to find defects in shafts, pipes, and other metal or plastic parts[10]
  • It can be used to detect objects in dark areas
  • It has some medical application, essentially in physiotherapy

Limitations and disadvantages of thermography

  • Quality cameras often have a high price range (often US$3,000 or more) due to the expense of the larger pixel array (state of the art 1024X720), while less expensive models (with pixel arrays of 40x40 up to 160x120 pixels) are also available. Fewer pixels reduce the image quality making it more difficult to distinguish proximate targets within the same field of view.
  • Many models do not provide the irradiance measurements used to construct the output image; the loss of this information without a correct calibration for emissivity, distance, and ambient temperature and relative humidity entails that the resultant images are inherently incorrect measurements of temperature[11]
  • Images can be difficult to interpret accurately when based upon certain objects, specifically objects with erratic temperatures, although this problem is reduced in active thermal imaging[12]
  • Accurate temperature measurements are hindered by differing emissivities and reflections from other surfaces[13]
  • Most cameras have ±2% accuracy or worse in measurement of temperature and are not as accurate as contact methods[7][8][9]
  • Only able to directly detect surface temperatures

Applications

Kite aerial thermogram of the site of Ogilface Castle, Scotland.
UAS Thermal Imagery processed by DroneMapper. Solar Panel Array, Switzerland
Thermal imaging cameras convert the energy in the infrared wavelength into a visible light display. All objects above absolute zero emit thermal infrared energy, so thermal cameras can passively see all objects, regardless of ambient light. However, most thermal cameras only see objects warmer than −50 °C ( -122 °F ).

The spectrum and amount of thermal radiation depend strongly on an object's surface temperature. This makes it possible for a thermal imaging camera to display an object's temperature. However, other factors also influence the radiation, which limits the accuracy of this technique. For example, the radiation depends not only on the temperature of the object, but is also a function of the emissivity of the object. Also, radiation originates from the surroundings and is reflected in the object, and the radiation from the object and the reflected radiation will also be influenced by the absorption of the atmosphere.

Standards

ASTM International (ASTM)
  • ASTM C1060, Standard Practice for Thermographic Inspection of Insulation Installations in Envelope Cavities of Frame Buildings
  • ASTM C1153, Standard Practice for the Location of Wet Insulation in Roofing Systems Using Infrared Imaging
  • ATSM D4788, Standard Test Method for Detecting Delamination in Bridge Decks Using Infrared Thermography
  • ASTM E1186, Standard Practices for Air Leakage Site Detection in Building Envelopes and Air Barrier Systems
  • ASTM E1934, Standard Guide for Examining Electrical and Mechanical Equipment with Infrared Thermography

Infraspection Institute
  • Standard for Infrared Inspection of Electrical Systems and Rotating Equipment
  • Standard for Infrared Inspection of Insulated Roofs
  • Standard for Infrared Inspection of Building Envelopes
  • Standard for Infrared Inspections to Detect Pests and Pest Related Damage
  • Standard for Infrared Inspection of Installed Photovoltaic (PV) Systems
  • Standard for Infrared Inspection of Recreational Yachts and Small Craft Constructed of Fiberglass Reinforced Plastic and Composite Materials
  • Standard for Infrared Thermal Imaging of Horses
  • Standard for Measuring and Compensating for Emittance Using Infrared Imaging Radiometers
  • Standard for Measuring and Compensating for Reflected Temperature Using Infrared Imaging Radiometers
  • Standard for Measuring and Compensating for Transmittance of an Attenuating Medium Using Infrared Imaging Radiometers
  • Standard for Measuring Distance/Target Size Values for Infrared Imaging Radiometers

International Organization for Standardization (ISO)
  • ISO 6781, Thermal insulation – Qualitative detection of thermal irregularities in building envelopes – Infrared method
  • ISO 18434-1, Condition monitoring and diagnostics of machines – Thermography – Part 1: General procedures
  • ISO 18436-7, Condition monitoring and diagnostics of machines – Requirements for qualification and assessment of personnel – Part 7: Thermography

Biological counterpart

Thermography by definition is by means of an instrument (artifact), but some living creatures have natural organs that function as counterparts to bolometers, and thus possess a crude type of thermal imaging capability (thermoception). One of the best known examples is infrared sensing in snakes.

Ice calving and Global Warming

From Wikipedia, the free encyclopedia

A mass of ice calves from the Perito Moreno Glacier

Ice calving, also known as glacier calving or iceberg calving, is the breaking of ice chunks from the edge of a glacier.[1] It is a form of ice ablation or ice disruption and is normally caused by the glacier expanding. It is the sudden release and breaking away of a mass of ice from a glacier, iceberg, ice front, ice shelf, or crevasse. The ice that breaks away can be classified as an iceberg, but may also be a growler, bergy bit, or a crevasse wall breakaway.[2]

Calving of glaciers is often accompanied by a loud cracking or booming sound[3] before blocks of ice up to 60 metres (200 ft) high break loose and crash into the water. The entry of the ice into the water causes large, and often hazardous waves.[4] The waves formed in locations like Johns Hopkins Glacier can be so large that boats cannot approach closer than 3 kilometres (1.9 mi). These events have become major tourist attractions in locations such as Alaska.

Many glaciers terminate at oceans or freshwater lakes which results naturally[5] with the calving of large numbers of icebergs. Calving of Greenland's glaciers produce 12,000 to 15,000 icebergs each year alone.[6]

Calving of ice shelves is usually preceded by a rift.[7] These events are not often observed.
Etymologically, calving is cognatic with calving as in bearing a calf.[8]

Causes

Video of iceberg calving in Greenland, 2007
A calving glacier and the resulting ice field.

It is useful to classify causes of calving into first, second, and third order processes.[9] First order processes are responsible for the overall rate of calving at the glacier scale. The first order cause of calving is longitudinal stretching, which controls the formation of crevasses. When crevasses penetrate the full thickness of the ice, calving will occur.[10] Longitudinal stretching is controlled by friction at the base and edges of the glacier, glacier geometry and water pressure at the bed. These factors, therefore, exert the primary control on calving rate.

Second and third order calving processes can be considered to be superimposed on the first order process above, and control the occurrence of individual calving events, rather than the overall rate. Melting at the waterline is an important second order calving process as it undercuts the subaerial ice, leading to collapse. Other second order processes include tidal and seismic events, buoyant forces and melt water wedging.

When calving occurs due to waterline melting, only the subaerial part of the glacier will calve, leaving a submerged 'foot'. Thus, a third order process is defined, whereby upward buoyant forces cause this ice foot to break off and emerge at the surface. This process is extremely dangerous, as it has been known to occur, without warning, up to 300m from the glacier terminus.[11]

Calving law

Though many factors that contribute to calving have been identified, a reliable predictive mathematical formula is still under development. Data is currently being assembled from ice shelves in Antarctica and Greenland to help establish a 'calving law'. Variables used in models include properties of the ice such as thickness, density, temperature, c-axis fabric, impurity loading, though 'ice front normal spreading stress', is likely the most important variable, however it is usually not measured.[citation needed]

There are currently several concepts upon which to base a predictive law. One theory states that the calving rate is primarily a function of the ratio of tensile stress to vertical compressive stress, i.e., the calving rate is a function of the ratio of the largest to smallest principle stress.[12] Another theory, based on preliminary research, shows that the calving rate increases as a power of the spreading rate near the calving front.[citation needed]

Major calving events

Landsat image of Jakobshavn Isbræ. The lines show the position of the calving front of the Jakobshavn Isbræ since 1851. The date of this image is 2001 and the calving front of the glacier can be seen at the 2001 line. The area stretching from the calving front to the sea (towards the bottom left corner) is the Ilulissat icefjord. Courtesy of NASA Space Observatory

Filchner-Ronne Ice Shelf

In October, 1988, the A-38 iceberg broke away from the Filchner-Ronne Ice Shelf. It was about 150 km x 50 km. A second calving occurred in May 2000 and created an iceberg 167 km x 32 km.

Amery Ice Shelf

A major calving event occurred in 1962 to 1963. Currently, there is a section at the front of the shelf referred to as the 'loose tooth'. This section, about 30 km by 30 km is moving at about 12 meters per day and is expected to eventually calve away.[13]

Ward Hunt Ice Shelf

The largest observed calving of an ice island happened at Ward Hunt Ice Shelf. Sometime between August 1961 and April 1962 almost 600 km2 of ice broke away.[14]

Ayles Ice Shelf

In 2005, nearly the entire shelf calved from the northern edge of Ellesmere Island. Since 1900, about 90% of Ellesmere Island's ice shelves have calved and floated away. This event was the biggest of its kind for at least the past 25 years. A total of 87.1 km2 (33.6 sq mi) of ice was lost in this event. The largest piece was 66.4 km2 (25.6 sq mi) in area, (slightly larger than the City of Manhattan.[15]

Larsen Ice Shelf

This large ice shelf, located in the Weddell Sea, extending along the east coast of Antarctic Peninsula, consists of three segments, two of which have calved. The Larsen B Ice Shelf calved and disintegrated in February 2002. Then in January 1995, the Larsen A Ice Shelf containing 3,250 km² of ice 220 m thick calved and disintegrated.

Jakobshavn Isbrae Glacier

Also known as the Ilulissat Glacier or Sermeq Kujalleq in western Greenland, in an ongoing event, 35 billion tonnes of icebergs calve off and pass out of the fjord every year.

Photographer James Balog and his team were examining this glacier in 2008 when their cameras caught a piece of glacier the size of the Lower Manhattan fall into the ocean.[16] The calving event lasted for 75 minutes, during which time the glacier retreated a full mile across a calving face three miles (five kilometers) wide. Adam LeWinter and Jeff Orlowski captured this footage, which is featured in the film Chasing Ice.

Glacier surfing

First conceived in 1995 by Ryan Casey while filming for IMAX, this sport involves a surfer being towed into range by a jet ski and waiting for a mass of ice to calve from a glacier.[17] Surfers can wait for several hours in the icy water for an event. When a glacier calves, the mass of ice can produce 8 metre waves. Rides of 300 metres lasting for one minute can be achieved.[18]

Saturday, March 25, 2017

Random Walks and Greenhouse Warming

https://en.wikipedia.org/wiki/Random_walk

I'm not the first to explore this issue, but it seems rarely covered.  The basics:  an IR photon emitted from the ground into an atmosphere without greenhouse gasses will head in a straight line to space, while molecules of greenhouse gasses like CO2 and H2O, as they are spinning and moving very fast, absorb and re-emit the photons in a random (or largely random) directions.  This greatly increases the time they spend in the atmosphere, making it warmer.  For example,


Trail of Tears

From Wikipedia, the free encyclopedia

The Trail of Tears Memorial at the New Echota Historic Site.

The Trail of Tears was a series of forced removals of Native American nations from their ancestral homelands in the Southeastern United States to an area west of the Mississippi River that had been designated as Native Territory. The forced relocations were carried out by various government authorities following the passage of the Indian Removal Act in 1830. The relocated people suffered from exposure, disease, and starvation while en route, and more than four thousand died before reaching their various destinations. The removal included members of the Cherokee, Muscogee, Seminole, Chickasaw, and Choctaw nations. The phrase "Trail of Tears" originated from a description of the removal of the Cherokee Nation in 1838.[1][2][3]

Between 1830 and 1850, the Chickasaw, Choctaw, Creek, Seminole, and Cherokee people (including Native Americans, and the African freedmen and slaves who lived among them) were forcibly removed from their traditional lands in the Southeastern United States, and relocated farther west.[4] Those Native Americans that were relocated were forced to march to their destinations by state and local militias.[5]

The Cherokee removal in 1838 (the last forced removal east of the Mississippi) was brought on by the discovery of gold near Dahlonega, Georgia in 1828, resulting in the Georgia Gold Rush.[6] Approximately 2,000-6,000 of the 16,543 relocated Cherokee perished along the way.[7][8][9][10][11]

Historical context

Map of United States Indian Removal, 1830-1835. Oklahoma is depicted in light yellow-green.

In 1830, a group of Indians collectively referred to as the Five Civilized Tribes, the Cherokee, Chickasaw, Choctaw, Muscogee, and Seminole, were living as autonomous nations in what would be later called the American Deep South. The process of cultural transformation, as proposed by George Washington and Henry Knox, was gaining momentum, especially among the Cherokee and Choctaw.[12]

American settlers had been pressuring the federal government to remove Indians from the Southeast; many settlers were encroaching on Indian lands, while others wanted more land made available to white settlers. Although the effort was vehemently opposed by many, including U.S. Congressman Davy Crockett of Tennessee, President Andrew Jackson was able to gain Congressional passage of the Indian Removal Act of 1830, which authorized the government to extinguish Indian title to lands in the Southeast.

In 1831, the Choctaw became the first Nation to be removed, and their removal served as the model for all future relocations. After two wars, many Seminoles were removed in 1832. The Creek removal followed in 1834, the Chickasaw in 1837, and lastly the Cherokee in 1838.[13] Many Indians remained in their ancestral homelands; some Choctaw are found in Mississippi, Creek in Alabama and Florida, Cherokee in North Carolina, and Seminole in Florida; a small group had moved to the Everglades and were never defeated by the government of the United States. A limited number of non-Indians, including some Africans (many as slaves, and others as spouses), also accompanied the Indians on the trek westward.[13] By 1837, 46,000 Indians from the southeastern states had been removed from their homelands, thereby opening 25 million acres (100,000 km2) for predominantly white settlement.[13]

Prior to 1830, the fixed boundaries of these autonomous tribal nations, comprising large areas of the United States, were subject to continual cession and annexation, in part due to pressure from squatters and the threat of military force in the newly declared U.S. territories—federally administered regions whose boundaries supervened upon the Native treaty claims. As these territories became U.S. states, state governments sought to dissolve the boundaries of the Indian nations within their borders, which were independent of state jurisdiction, and to expropriate the land therein. These pressures were exacerbated by U.S. population growth and the expansion of slavery in the South, with the rapid development of cotton cultivation in the uplands following the invention of the cotton gin.[14]

Jackson's role

The removals, conducted under Presidents Andrew Jackson and Martin Van Buren, followed the Indian Removal Act of 1830. The Act provided the President with powers to exchange land with Native tribes and provide infrastructure improvements on the existing lands. The law also gave the president power to pay for transportation costs to the West, should tribes choose to relocate. The law did not, however, allow the President to force tribes to move West without a mutually agreed-upon treaty.[15]

In the years following the Act, the Cherokee filed several lawsuits regarding conflicts with the state of Georgia. Some of these cases reached the Supreme Court, the most influential being Worcester v. Georgia (1832). Samuel Worcester and other non-Indians were convicted by Georgia law for residing in Cherokee territory in the state of Georgia, without a license. Worcester was sentenced to prison for four years and appealed the ruling, arguing that this sentence violated treaties made between Indian nations and the United States federal government by imposing state laws on Cherokee lands. The Court ruled in Worcester's favor, declaring that the Cherokee Nation was subject only to federal law and that the Supremacy Clause barred legislative interference by the state of Georgia. Chief Justice Marshall argued, "The Cherokee nation, then, is a distinct community occupying its own territory in which the laws of Georgia can have no force. The whole intercourse between the United States and this Nation, is, by our constitution and laws, vested in the government of the United States."[16][17]

Andrew Jackson did not listen to the Supreme Court mandate barring Georgia from intruding on Cherokee lands. He feared that enforcement would lead to open warfare between federal troops and the Georgia militia, which would compound the ongoing crisis in South Carolina and lead to a broader civil war. Instead, he vigorously negotiated a land exchange treaty with the Cherokee.[18] Political opponents Henry Clay and John Quincy Adams, who supported the Worcester decision, were outraged by Jackson’s refusal to uphold Cherokee claims against the state of Georgia.[19] Ralph Waldo Emerson wrote an account of Cherokee assimilation into the American culture, declaring his support of the Worcester decision.[20][21]

Jackson chose to continue with Indian removal, and negotiated The Treaty of New Echota, on December 29, 1835, which granted Cherokee Indians two years to move to Indian Territory (modern Oklahoma). Only a fraction of the Cherokees left voluntarily. The U.S. government, with assistance from state militias, forced most of the remaining Cherokees west in 1838.[22] The Cherokees were temporarily remanded in camps in eastern Tennessee. In November, the Cherokee were broken into groups of around 1,000 each and began the journey west. They endured heavy rains, snow, and freezing temperatures.

When the Cherokee negotiated the Treaty of New Echota, they exchanged all their land east of the Mississippi for land in modern Oklahoma and a $5 million payment from the federal government. Many Cherokee felt betrayed that their leadership accepted the deal, and over 16,000 Cherokee signed a petition to prevent the passage of the treaty. By the end of the decade in 1840, tens of thousands of Cherokee and other tribes had been removed from their land east of the Mississippi River. The Creek, Choctaw, Seminole, and Chicksaw were also relocated under the Indian Removal Act of 1830. One Choctaw leader portrayed the removal as "A Trail of Tears and Deaths", a devastating event that removed most of the Native population of the southeastern United States from their traditional homelands.[23]

Terminology

The latter forced relocations have sometimes been referred to as "death marches", in particular with reference to the Cherokee march across the Midwest in 1838, which occurred on a predominantly land route.[14]

Indians who had the means initially provided for their own removal. Contingents that were led by conductors from the U.S. Army included those led by Edward Deas, who was claimed to be a sympathizer for the Cherokee plight.[citation needed] The largest death toll from the Cherokee forced relocation comes from the period after the May 23, 1838 deadline. This was at the point when the remaining Cherokee were rounded into camps and pressed into oversized detachments, often over 700 in size (larger than the populations of Little Rock or Memphis at that time). Communicable diseases spread quickly through these closely quartered groups, killing many. These contingents were among the last to move, but following the same routes the others had taken; the areas they were going through had been depleted of supplies due to the vast numbers that had gone before them. The marchers were subject to extortion and violence along the route. In addition, these final contingents were forced to set out during the hottest and coldest months of the year, killing many. Exposure to the elements, disease and starvation, harassment by local frontiersmen, and insufficient rations similarly killed up to one-third of the Choctaw and other nations on the march.[24]

There exists some debate among historians and the affected tribes as to whether the term "Trail of Tears" should be used to refer to the entire history of forced relocations from the United States east of the Mississippi into Indian Territory (as was the stated U.S. policy), or to the Five Tribes described above, to the route of the land march specifically, or to specific marches in which the remaining holdouts from each area were rounded up.

Legal background

The territorial boundaries claimed as sovereign and controlled by the Indian nations living in what were then known as the Indian Territories—the portion of the early United States west of the Mississippi River not yet claimed or allotted to become Oklahoma—were fixed and determined by national treaties with the United States federal government. These recognized the tribal governments as dependent but internally sovereign, or autonomous nations under the sole jurisdiction of the federal government.
While retaining their tribal governance, which included a constitution or official council in tribes such as the Iroquois and Cherokee, many portions of the southeastern Indian nations had become partially or completely economically integrated into the economy of the region. This included the plantation economy in states such as Georgia, and the possession of slaves. These slaves were also forcibly relocated during the process of removal.[14] A similar process had occurred earlier in the territories controlled by the Confederacy of the Six Nations in what is now upstate New York prior to the British invasion and subsequent U.S. annexation of the Iroquois nation.

Under the history of U.S. treaty law, the territorial boundaries claimed by federally recognized tribes received the same status under which the Southeastern tribal claims were recognized; until the following establishment of reservations of land, determined by the federal government, which were ceded to the remaining tribes by de jure treaty, in a process that often entailed forced relocation. The establishment of the Indian Territory and the extinguishment of Indian land claims east of the Mississippi anticipated the establishment of the U.S. Indian reservation system. It was imposed on remaining Indian lands later in the 19th century.

The statutory argument for Indian sovereignty persisted until the Supreme Court of the United States ruled in Cherokee Nation v. Georgia (1831), that (e.g.) the Cherokee were not a sovereign and independent nation, and therefore not entitled to a hearing before the court. However, in Worcester v. Georgia (1832), the court re-established limited internal sovereignty under the sole jurisdiction of the federal government, in a ruling that both opposed the subsequent forced relocation and set the basis for modern U.S. case law.

While the latter ruling was defied by Jackson,[25] the actions of the Jackson administration were not isolated because state and federal officials had violated treaties without consequence, often attributed to military exigency, as the members of individual Indian nations were not automatically United States citizens and were rarely given standing in any U.S. court.

Jackson's involvement in what became known as the Trail of Tears cannot be ignored. In a speech regarding Indian removal, Jackson said, "It will separate the Indians from immediate contact with settlements of whites; free them from the power of the States; enable them to pursue happiness in their own way and under their own rude institutions; will retard the progress of decay, which is lessening their numbers, and perhaps cause them gradually, under the protection of the Government and through the influence of good counsels, to cast off their savage habits and become an interesting, civilized, and Christian community.” According to Jackson, the move would be nothing but beneficial for all parties. His point of view garnered support from many Americans, many of whom would benefit economically from the removal.

This was compounded by the fact that while citizenship tests existed for Indians living in newly annexed areas before and after forced relocation, individual U.S. states did not recognize tribal land claims, only individual title under State law, and distinguished between the rights of white and non-white citizens, who often had limited standing in court; and Indian removal was carried out under U.S. military jurisdiction, often by state militias. As a result, individual Indians who could prove U.S. citizenship were nevertheless displaced from newly annexed areas.[14] The military actions and subsequent treaties enacted by Jackson's and Martin Van Buren's administrations pursuant to the 1830 law, which Tennessee Congressman Davy Crockett had unsuccessfully voted against,[26] are widely considered to have directly caused the expulsion or death of a substantial part of the Indians then living in the southeastern United States.

Choctaw removal


The Choctaw nation occupied large portions of what are now the U.S. states of Alabama, Mississippi, and Louisiana. After a series of treaties starting in 1801, the Choctaw nation was reduced to 11,000,000 acres (45,000 km2). The Treaty of Dancing Rabbit Creek ceded the remaining country to the United States and was ratified in early 1831. The removals were only agreed to after a provision in the Treaty of Dancing Rabbit Creek allowed some Choctaw to remain. George W. Harkins wrote to the citizens of the United States before the removals were to commence:
It is with considerable diffidence that I attempt to address the American people, knowing and feeling sensibly my incompetency; and believing that your highly and well improved minds would not be well entertained by the address of a Choctaw. But having determined to emigrate west of the Mississippi river this fall, I have thought proper in bidding you farewell to make a few remarks expressive of my views, and the feelings that actuate me on the subject of our removal.... We as Choctaws rather chose to suffer and be free, than live under the degrading influence of laws, which our voice could not be heard in their formation.
— George W. Harkins, George W. Harkins to the American People[27]
United States Secretary of War Lewis Cass appointed George Gaines to manage the removals. Gaines decided to remove Choctaws in three phases starting in 1831 and ending in 1833. The first was to begin on November 1, 1831 with groups meeting at Memphis and Vicksburg. A harsh winter would batter the emigrants with flash floods, sleet, and snow. Initially the Choctaws were to be transported by wagon but floods halted them. With food running out, the residents of Vicksburg and Memphis were concerned. Five steamboats (the Walter Scott, the Brandywine, the Reindeer, the Talma, and the Cleopatra) would ferry Choctaws to their river-based destinations. The Memphis group traveled up the Arkansas for about 60 miles (100 km) to Arkansas Post. There the temperature stayed below freezing for almost a week with the rivers clogged with ice, so there could be no travel for weeks. Food rationing consisted of a handful of boiled corn, one turnip, and two cups of heated water per day. Forty government wagons were sent to Arkansas Post to transport them to Little Rock. When they reached Little Rock, a Choctaw chief referred to their trek as a "trail of tears and death."[28] The Vicksburg group was led by an incompetent guide and was lost in the Lake Providence swamps.
Alexis de Tocqueville, French political thinker and historian

Alexis de Tocqueville, the French philosopher, witnessed the Choctaw removals while in Memphis, Tennessee in 1831,
In the whole scene there was an air of ruin and destruction, something which betrayed a final and irrevocable adieu; one couldn't watch without feeling one's heart wrung. The Indians were tranquil, but sombre and taciturn. There was one who could speak English and of whom I asked why the Chactas were leaving their country. "To be free," he answered, could never get any other reason out of him. We ... watch the expulsion ... of one of the most celebrated and ancient American peoples.
— Alexis de Tocqueville, Democracy in America[29]
Nearly 17,000 Choctaws made the move to what would be called Indian Territory and then later Oklahoma.[30] About 2,500–6,000 died along the trail of tears. Approximately 5,000–6,000 Choctaws remained in Mississippi in 1831 after the initial removal efforts.[24][31] The Choctaws who chose to remain in newly formed Mississippi were subject to legal conflict, harassment, and intimidation. The Choctaws "have had our habitations torn down and burned, our fences destroyed, cattle turned into our fields and we ourselves have been scourged, manacled, fettered and otherwise personally abused, until by such treatment some of our best men have died."[31] The Choctaws in Mississippi were later reformed as the Mississippi Band of Choctaw Indians and the removed Choctaws became the Choctaw Nation of Oklahoma. The Choctaws were the first to sign a removal treaty presented by the federal government. President Andrew Jackson wanted strong negotiations with the Choctaws in Mississippi, and the Choctaws seemed much more cooperative than Andrew Jackson had imagined. When commissioners and Choctaws came to negotiation agreements it was said the United States would bear the expense of moving their homes and that they had to be removed within two and a half years of the signed treaty.[32]

Seminole resistance

The U.S. acquired Florida from Spain via the Adams–Onís Treaty and took possession in 1821. In 1832 the Seminoles were called to a meeting at Payne's Landing on the Ocklawaha River. The treaty negotiated called for the Seminoles to move west, if the land were found to be suitable. They were to be settled on the Creek reservation and become part of the Creek tribe, who considered them deserters; some of the Seminoles had been derived from Creek bands but also from other tribes. Those among the tribe who once were members of Creek bands did not wish to move west to where they were certain that they would meet death for leaving the main band of Creek Indians. The delegation of seven chiefs who were to inspect the new reservation did not leave Florida until October 1832. After touring the area for several months and conferring with the Creeks who had already settled there, the seven chiefs signed a statement on March 28, 1833 that the new land was acceptable. Upon their return to Florida, however, most of the chiefs renounced the statement, claiming that they had not signed it, or that they had been forced to sign it, and in any case, that they did not have the power to decide for all the tribes and bands that resided on the reservation. The villages in the area of the Apalachicola River were more easily persuaded, however, and went west in 1834.[33] On December 28, 1835 a group of Seminoles and blacks ambushed a U.S. Army company marching from Fort Brooke in Tampa to Fort King in Ocala, killing all but three of the 110 army troops. This came to be known as the Dade Massacre.
Seminole warrior Tuko-see-mathla, 1834

As the realization that the Seminoles would resist relocation sank in, Florida began preparing for war. The St. Augustine Militia asked the War Department for the loan of 500 muskets. Five hundred volunteers were mobilized under Brig. Gen. Richard K. Call. Indian war parties raided farms and settlements, and families fled to forts, large towns, or out of the territory altogether. A war party led by Osceola captured a Florida militia supply train, killing eight of its guards and wounding six others. Most of the goods taken were recovered by the militia in another fight a few days later. Sugar plantations along the Atlantic coast south of St. Augustine were destroyed, with many of the slaves on the plantations joining the Seminoles.[34]

Other warchiefs such as Halleck Tustenuggee, Jumper, and Black Seminoles Abraham and John Horse continued the Seminole resistance against the army. The war ended, after a full decade of fighting, in 1842. The U.S. government is estimated to have spent about $20,000,000 on the war, at the time an astronomical sum, and equal to $496,344,828 today. Many Indians were forcibly exiled to Creek lands west of the Mississippi; others retreated into the Everglades. In the end, the government gave up trying to subjugate the Seminole in their Everglades redoubts and left fewer than 100 Seminoles in peace. However, other scholars state that at least several hundred Seminoles remained in the Everglades after the Seminole Wars.[35][36][37]

As a result of the Seminole Wars, the surviving Seminole band of the Everglades claims to be the only federally recognized tribe which never relinquished sovereignty or signed a peace treaty with the United States.

In general the American people tended to view the Indian resistance as unwarranted. An article published by the Virginia Enquirer on January 26, 1836, called the "Hostilities of the Seminoles", assigned all the blame for the violence that came from the Seminole's resistance to the Seminoles themselves. The article accuses the Indians of not staying true to their word—the promises they supposedly made in the treaties and negotiations from the Indian Removal Act.[38]

Creek dissolution

Selocta (or Shelocta) was a Muscogee chief who appealed to Andrew Jackson to reduce the demands for Creek lands at the signing of the Treaty of Fort Jackson

After the War of 1812, some Muscogee leaders such as William McIntosh signed treaties that ceded more land to Georgia. The 1814 signing of the Treaty of Fort Jackson signaled the end for the Creek Nation and for all Indians in the South.[39] Friendly Creek leaders, like Selocta and Big Warrior, addressed Sharp Knife (the Indian nickname for Andrew Jackson) and reminded him that they keep the peace. Nevertheless, Jackson retorted that they did not "cut (Tecumseh's) throat" when they had the chance, so they must now cede Creek lands. Jackson also ignored Article 9 of the Treaty of Ghent that restored sovereignty to Indians and their nations.
Jackson opened this first peace session by faintly acknowledging the help of the friendly Creeks. That done, he turned to the Red Sticks and admonished them for listening to evil counsel. For their crime, he said, the entire Creek Nation must pay. He demanded the equivalent of all expenses incurred by the United States in prosecuting the war, which by his calculation came to 23,000,000 acres (93,000 km2) of land. - Robert V. Remini, Andrew Jackson[39]
Eventually, the Creek Confederacy enacted a law that made further land cessions a capital offense. Nevertheless, on February 12, 1825, McIntosh and other chiefs signed the Treaty of Indian Springs, which gave up most of the remaining Creek lands in Georgia.[40] After the U.S. Senate ratified the treaty, McIntosh was assassinated on May 13, 1825, by Creeks led by Menawa.

The Creek National Council, led by Opothle Yohola, protested to the United States that the Treaty of Indian Springs was fraudulent. President John Quincy Adams was sympathetic, and eventually the treaty was nullified in a new agreement, the Treaty of Washington (1826).[41] The historian R. Douglas Hurt wrote: "The Creeks had accomplished what no Indian nation had ever done or would do again — achieve the annulment of a ratified treaty."[42] However, Governor Troup of Georgia ignored the new treaty and began to forcibly remove the Indians under the terms of the earlier treaty. At first, President Adams attempted to intervene with federal troops, but Troup called out the militia, and Adams, fearful of a civil war, conceded. As he explained to his intimates, "The Indians are not worth going to war over."

Although the Creeks had been forced from Georgia, with many Lower Creeks moving to the Indian Territory, there were still about 20,000 Upper Creeks living in Alabama. However, the state moved to abolish tribal governments and extend state laws over the Creeks. Opothle Yohola appealed to the administration of President Andrew Jackson for protection from Alabama; when none was forthcoming, the Treaty of Cusseta was signed on March 24, 1832, which divided up Creek lands into individual allotments.[43] Creeks could either sell their allotments and receive funds to remove to the west, or stay in Alabama and submit to state laws. The Creeks were never given a fair chance to comply with the terms of the treaty, however. Rampant illegal settlement of their lands by Americans continued unabated with federal and state authorities unable or unwilling to do much to halt it. Further, as recently detailed by historian Billy Winn in his thorough chronicle of the events leading to removal, a variety of fraudulent schemes designed to cheat the Creeks out of their allotments, many of them organized by speculators operating out of Columbus, Georgia and Montgomery, Alabama, were perpetrated after the signing of the Treaty of Cusseta.[44] A portion of the beleaguered Creeks, many desperately poor and feeling abused and oppressed by their American neighbors, struck back by carrying out occasional raids on area farms and committing other isolated acts of violence. Escalating tensions erupted into open war with the United States following the destruction of the village of Roanoke, Georgia, located along the Chattahoochee River on the boundary between Creek and American territory, in May 1836. During the so-called "Creek War of 1836" Secretary of War Lewis Cass dispatched General Winfield Scott to end the violence by forcibly removing the Creeks to the Indian Territory west of the Mississippi River. With the Indian Removal Act of 1830 it continued into 1835 and after as in 1836 over 15,000 Creeks were driven from their land for the last time. 3,500 of those 15,000 Creeks did not survive the trip to Oklahoma where they eventually settled.[23]

Chickasaw monetary removal

Historic Marker in Marion, Arkansas, for the Trail of Tears
Fragment of the Trail of Tears still intact at Village Creek State Park, Arkansas (2010)

The Chickasaw received financial compensation from the United States for their lands east of the Mississippi River. In 1836, the Chickasaws had reached an agreement to purchase land from the previously removed Choctaws after a bitter five-year debate. They paid the Choctaws $530,000 (equal to $11,558,818 today) for the westernmost part of the Choctaw land. The first group of Chickasaws moved in 1836 and was led by John M. Millard. The Chickasaws gathered at Memphis on July 4, 1836, with all of their assets—belongings, livestock, and slaves. Once across the Mississippi River, they followed routes previously established by the Choctaws and the Creeks. Once in Indian Territory, the Chickasaws merged with the Choctaw nation.

Cherokee forced relocation

Cherokee Principal Chief John Ross, photographed before his death in 1866

By 1838, about 2,000 Cherokee had voluntarily relocated from Georgia to Indian Territory (present day Oklahoma). Forcible removals began in May 1838 when General Winfield Scott received a final order from President Martin Van Buren to relocate the remaining Cherokees.[23] Approximately 4,000 Cherokees died in the ensuing trek to Oklahoma.[45] In the Cherokee language, the event is called nu na da ul tsun yi (“the place where they cried”) or nu na hi du na tlo hi lu i (the trail where they cried). The Cherokee Trail of Tears resulted from the enforcement of the Treaty of New Echota, an agreement signed under the provisions of the Indian Removal Act of 1830, which exchanged Indian land in the East for lands west of the Mississippi River, but which was never accepted by the elected tribal leadership or a majority of the Cherokee people.

The sparsely inhabited Cherokee lands were highly attractive to Georgian farmers experiencing population pressure, and illegal settlements resulted. Long-simmering tensions between Georgia and the Cherokee Nation were brought to a crisis by the discovery of gold near Dahlonega, Georgia, in 1829, resulting in the Georgia Gold Rush, the second gold rush in U.S. history. Hopeful gold speculators began trespassing on Cherokee lands, and pressure mounted to fulfill the Compact of 1802 in which the US Government promised to extinguish Indian land claims in the state of Georgia.

When Georgia moved to extend state laws over Cherokee lands in 1830, the matter went to the U.S. Supreme Court. In Cherokee Nation v. Georgia (1831), the Marshall court ruled that the Cherokee Nation was not a sovereign and independent nation, and therefore refused to hear the case. However, in Worcester v. Georgia (1832), the Court ruled that Georgia could not impose laws in Cherokee territory, since only the national government — not state governments — had authority in Indian affairs. Worcester v Georgia is associated with Andrew Jackson's famous, though apocryphal, quote "John Marshall has made his decision; now let him enforce it!" In reality, this quote did not appear until 30 years after the incident and was first printed in a textbook authored by Jackson critic Horace Greeley.[18]
Elizabeth "Betsy" Brown Stephens (1903), a Cherokee Indian who walked the Trail of Tears in 1838

Fearing open warfare between federal troops and the Georgia militia, Jackson decided not to enforce Cherokee claims against the state of Georgia. He was already embroiled in a constitutional crisis with South Carolina (i.e. the nullification crisis) and favored Cherokee relocation over civil war.[18] With the Indian Removal Act of 1830, the U.S. Congress had given Jackson authority to negotiate removal treaties, exchanging Indian land in the East for land west of the Mississippi River. Jackson used the dispute with Georgia to put pressure on the Cherokees to sign a removal treaty.[46]

The final treaty, passed in Congress by a single vote, and signed by President Andrew Jackson, was imposed by his successor President Martin Van Buren. Van Buren allowed Georgia, Tennessee, North Carolina, and Alabama an armed force of 7,000 militiamen, army regulars, and volunteers under General Winfield Scott to relocate about 13,000 Cherokees to Cleveland, Tennessee. After the initial roundup, the U.S. military oversaw the emigration to Oklahoma. Former Cherokee lands were immediately opened to settlement. Most of the deaths during the journey were caused by disease, malnutrition, and exposure during an unusually cold winter.[47]

In the winter of 1838 the Cherokee began the 1,000-mile (1,600 km) march with scant clothing and most on foot without shoes or moccasins. The march began in Red Clay, Tennessee, the location of the last Eastern capital of the Cherokee Nation. Because of the diseases, the Indians were not allowed to go into any towns or villages along the way; many times this meant traveling much farther to go around them.[48] After crossing Tennessee and Kentucky, they arrived at the Ohio River across from Golconda in southern Illinois about the 3rd of December 1838. Here the starving Indians were charged a dollar a head (equal to $22.49 today) to cross the river on "Berry's Ferry" which typically charged twelve cents, equal to $2.70 today. They were not allowed passage until the ferry had serviced all others wishing to cross and were forced to take shelter under "Mantle Rock," a shelter bluff on the Kentucky side, until "Berry had nothing better to do". Many died huddled together at Mantle Rock waiting to cross. Several Cherokee were murdered by locals. The Cherokee filed a lawsuit against the U.S. Government through the courthouse in Vienna, suing the government for $35 a head (equal to $787.17 today) to bury the murdered Cherokee.[48]

As they crossed southern Illinois, on December 26, Martin Davis, Commissary Agent for Moses Daniel's detachment, wrote: "There is the coldest weather in Illinois I ever experienced anywhere. The streams are all frozen over something like 8 or 12 inches [20 or 30 cm] thick. We are compelled to cut through the ice to get water for ourselves and animals. It snows here every two or three days at the fartherest. We are now camped in Mississippi [River] swamp 4 miles (6 km) from the river, and there is no possible chance of crossing the river for the numerous quantity of ice that comes floating down the river every day. We have only traveled 65 miles (105 km) on the last month, including the time spent at this place, which has been about three weeks. It is unknown when we shall cross the river...."[49]
I fought through the War Between the States and have seen many men shot, but the Cherokee Removal was the cruelest work I ever knew.
— Georgian soldier who participated in the removal[50]
A Trail of Tears map of Southern Illinois from the USDA - U.S. Forest Service

It eventually took almost three months to cross the 60 miles (97 kilometres) on land between the Ohio and Mississippi Rivers.[51] The trek through southern Illinois is where the Cherokee suffered most of their deaths. However a few years before forced removal, some Cherokee who opted to leave their homes voluntarily chose a water-based route through the Tennessee, Ohio and Mississippi rivers. It took only 21 days, but the Cherokee who were forcibly relocated were weary of water travel.[52]

Removed Cherokees initially settled near Tahlequah, Oklahoma. When signing the Treaty of New Echota in 1835 Major Ridge said "I have signed my death warrant." The resulting political turmoil led to the killings of Major Ridge, John Ridge, and Elias Boudinot; of the leaders of the Treaty Party, only Stand Watie escaped death.[53][54][55] The population of the Cherokee Nation eventually rebounded, and today the Cherokees are the largest American Indian group in the United States.[56]

There were some exceptions to removal. Perhaps 100 Cherokees evaded the U.S. soldiers and lived off the land in Georgia and other states. Those Cherokees who lived on private, individually owned lands (rather than communally owned tribal land) were not subject to removal. In North Carolina, about 400 Cherokees, known as the Oconaluftee Cherokee, lived on land in the Great Smoky Mountains owned by a white man named William Holland Thomas (who had been adopted by Cherokees as a boy), and were thus not subject to removal. Added to this were some 200 Cherokee from the Nantahala area allowed to stay in the Qualla Boundary after assisting the U.S. Army in hunting down and capturing the family of the old prophet, Tsali. (Tsali faced a firing squad.) These North Carolina Cherokees became the Eastern Band of the Cherokee Nation.

Landmarks and references

Map of National Historic trails

In 1987, about 2,200 miles (3,500 km) of trails were authorized by federal law to mark the removal of 17 detachments of the Cherokee people.[57] Called the "Trail of Tears National Historic Trail," it traverses portions of nine states and includes land and water routes.[58]

Trail of Tears outdoor historical drama, Unto These Hills

An historical drama based on the Trail of Tears, Unto These Hills written by Kermit Hunter, has sold over five million tickets for its performances since its opening on July 1, 1950, both touring and at the outdoor Mountainside Theater of the Cherokee Historical Association in Cherokee, North Carolina.[59][60]

Commemorative medallion

Cherokee artist Troy Anderson was commissioned to design the Cherokee Trail of Tears Sesquicentennial Commemorative Medallion. The falling-tear medallion shows a seven-pointed star, the symbol of the seven clans of the Cherokees.[61]

In literature and oral history

  • Family Stories From the Trail of Tears is a collection edited by Lorrie Montiero and transcribed by Grant Foreman, taken from the Indian-Pioneer History Collection[62]
  • Walking the Trail (1991) is a book by Jerry Ellis describing his 900-mile walk retracing of the Trail of Tears in reverse

Operator (computer programming)

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