Locating Cemeteries and Gravesites (5)
By Kristin J. Wilson, Physical Anthropologist/Archaeologist
Although you can identify many apparently unmarked graves simply by looking for rectangular depressions on the ground surface or for intentionally placed fieldstones, other historic burials are more difficult to locate. Most historic cemeteries contain unmarked graves. When development, improvements, additional interments, or even relocation, threatens a historic cemetery, it is important to find and document all existing graves to prevent accidental intrusion.
One of the most effective, minimally invasive methods for located unmarked graves is systematic probing. Historic sources tell us that pioneers used probing to locate existing interments before burying their loved ones in a family graveyard or rural cemetery. Probing detects softer areas where the ground has been disturbed. The surrounding, intact soil remains more compacted. Archaeologists have been using the method for the last 25 years or so to good effect. In fact, some states, like Georgia, have laws that require archaeologists to locate all graves and delineate the boundaries of historic cemeteries slated for development.
To probe for unmarked graves, you will need a metal probe measuring 3 to 3 ½ feet in length and 1/8 inch in diameter. It is best to use a probe fitted for replaceable steel tips since the tips wear out quickly. These items are available at environmental supply companies like Ben Meadows (http://www.benmeadows.com) for under $30. Do not use longer probes or augers as they may penetrate the coffin chambers and contact human remains. Despite common belief, historic graves are rarely as deep as six feet.
Before starting, be sure to obtain permission to probe the cemetery from the appropriate authorities, such as church officials, city managers, or descendants of those interred. If possible, ask a qualified archaeologist to demonstrate the technique. Keep safety in mind, also. Wear sturdy shoes. Some people prefer to wear gloves or to pad the probe handle with foam pipe insulation to cushion the hands.
Since most historic graves are oriented east-west with the head to the west (reflecting the Christian belief that the dead will face the rising sun on Judgment Day), the probe transects should be oriented north-south to maximize the chances of locating a soil anomaly (possible grave shaft). Set up your starting positions beyond the boundaries of the cemetery or area that you wish to investigate.
Probe transects should not be more than three or four feet apart. Closer interval testing will reduce the chances of missing small child or infant graves. Push the probe into the ground at 6-12 inch intervals feeling for soft spots. It is helpful to probe known graves as well as areas where there are no graves to get a feel for the difference. When you encounter a soft area, probe around it and try to determine the shape of the anomaly. Round or oval areas are often rotted trees or rodent burrows. Rectangular east-west oriented graves are more likely graves. When you find a grave, find a way to mark that location. Metal spikes in the four corners of the grave work well, because they are easy to find later using metal detectors. Plastic flagging or string will often deteriorate, but they work well for temporary identification purposes.
Once you locate all the possible unmarked graves, put them on a map, or better yet, have a registered surveyor create a certified map. File the information with your local land records office so that those burial locations are not lost again.
Ground Penetrating Radar (G.P.R.)
Ground penetrating radar surveys are useful for grave location. This method can locate the coffin, the person, objects buried with the person, or the burial trench into which the coffin or body was placed. Ground penetrating radar (GPR) is operated above the ground surface, and produces a cross-sectional image on the screen of the grave location that is underground. Unfortunately, badly decomposed bodies or those who are buried in wood coffins are extremely difficult to find. It is easier if bodies have things like belt or boot buckles.
You can scrape the soil down about one foot over the area you want to check and look for burial shafts. When the dirt is taken out and returned there is a color difference. 20 acres is a bit much for this technique.
Dowsing, also known as rhabdomancy, divining, water witching, or doodlebugging, is an old practice of finding water or minerals by the means of a dowsing rod. A dowsing rod is traditionally a forked stick which is held firmly in one's hands in a way that allows the rod to swing up or down at the slightest impulse, supposedly indicating the presence of the sought-after material. The mechanism behind the detection is believed to depend on energy fields hitherto unknown to science. The hypothesis is that these energy fields are emitted by all objects at different frequencies and intensities. The origin of the practice is not clear, but the earliest sign of its usage dates from a 4500-5000 year old grave inscription in Brittany.
The subject of grave dowsing has been much discussed and Saving Graves chooses not to enter into the debate. However, we feel it may be of some help to offer the following points regarding the subject:
1. In virtually every case where someone who uses this method is asked to explain scientifically how the process works, they have no idea, but they know that it works for them.
2. Many people may not aware of the many Scientific studies and experiments, all of which disproves dowsing capabilities. In one such study conducted in 1986, University Physicists from the University of Munich and the Technical University of Munich in Munich Germany spent 400,000 German marks (about $250,000.00) testing the dowsing theory. The results provide the most convincing disproof imaginable that dowsers can do what they claim. In fact, the results showed that the dowsers would have done better had they left their rods at home and guessed in the experiments. For the complete story as published in the January 1999 issue of Skeptical Inquirer, see http://www.csicop.org/si/9901/dowsing.html.
For additional information on the subject, we recommend the following link:
Dowsing - Science or Humbug?
The use of GPS provides one of the best means we currently have for preserving the locations of old abandoned graveyards.
WHAT IS IT?The Global Positioning System (GPS) is a satellite-based navigation system made up of a network of 24 satellites placed into orbit by the U.S. Department of Defense, orbiting the earth about 12,000 miles above us. They are constantly moving, making two complete orbits in less than 24 hours. These satellites are travelling at speeds of roughly 7,000 miles an hour. GPS satellites are powered by solar energy. They have backup batteries onboard to keep them running in the event of a solar eclipse, when there's no solar power. Small rocket boosters on each satellite keep them flying in the correct path. The satellite orbits are calculated to provide continuous global coverage; with all 24 satellites in operation, the necessary four satellites are in view of a GPS receiver 100% of the time. On average, eight satellites are present above the horizon at any given time.
Because GPS satellites can break down and their orbits are subject to drift, the Global Positioning System also includes a set of ground stations around the earth that monitor the satellites' operation and location. The ground stations relay information to a master ground station, which then sends updated information back to the satellites so that they can send more accurate signals to GPS receivers on earth.
GPS works in any weather conditions, anywhere in the world, 24 hours a day. The full constellation of 24 satellites was achieved in 1994. Each satellite weighs approximately 2,000 pounds and is about 17 feet across with the solar panels extended. transmitted power is less than 50 watts and they are built to last about 10 years. Replacements are constantly being built and launched into orbit. There are no subscription fees or setup charges to use GPS.The following websites offer
- GPS Primer
An excellent illustrated resource about GPS. Includes nine pages of content plus images, from the Aerospace Corporation.
- US Naval Observatory
- Global Positioning System Overview
A very thorough overview of GPS.
THE HISTORY OF GPS
The United States Department of Defense began work on the current GPS system early in the 1970's, when satellite technology made it feasible to provide the military with continous global coverage. The first GPS satellite was launched in 1978, and the system was declared fully operational in July of 1995. ln the 1980s, the government made the system available for civilian use. GPS works in any weather conditions, anywhere in the world, 24 hours a day.
In 1996 the National Security Council published the following goals for the GPS system:
- To strengthen and maintain national security.
- To encourage acceptance and integration of GPS into peaceful civil, commercial and scientific applications worldwide.
- To encourage private sector investment in and use of U.S. GPS technologies and services.
- To promote safety and efficiency in transportation and other fields.
- To promote international cooperation in using GPS for peaceful purposes.
- To advance U.S. scientific and technical capabilities.
On March 29, 1996, a Presidential Decision Directive (PDD) was signed by President Clinton that described GPS as an international information utility. The PDD included the following directives:
- The U.S. government will continue to operate, maintain and provide basic GPS signals worldwide, free of direct user fees.
- The U.S. will advocate the acceptance of GPS and it's augmentations as a standard for use by initiating international discussions and agreement with Japan and Europe.
The United States government permits worldwide, continuous access to GPS signals, free of charge. And, since the GPS system became operational in 1995, the development of "civil, commercial and scientific applications" has proceeded at breakneck speed. The development of these applications in 2000 and beyond will be particularly exciting because the United States government has abandoned its policy of "Selective Availability." Under this policy, civilian users of GPS could only pinpoint their location to within about 100 meters (330 feet). As of May, 2000, however, civilian users can obtain the same accuracy as military GPS users. This means that all GPS applications will be able to pinpoint a location to within 20 meters (66 feet).
A full history of the GPS system can be found at the GPS History, Chronology & Budgets website located at http://www.rand.org/publications/MR/MR614/MR614.appb.pdf (PDF)
HOW GPS OPERATES
GPS satellites circle the earth twice a day in a very precise orbit and transmit signal information to earth. GPS receivers take this information and use triangulation to calculate the user's exact location by the use of longitude and latitude information. Essentially, the GPS receiver compares the time a signal was transmitted by a satellite with the time it was received. The time difference tells the GPS receiver how far away the satellite is. Now, with measurements from a few more satellites, the receiver can determine the user's position and display it on the unit's electronic map. Today's GPS receivers are extremely accurate, and they maintain strong locks, even in dense foliage or urban settings with tall buildings. Certain atmospheric factors and other sources of error can affect the accuracy of GPS receivers. GARMIN GPS receivers are accurate to within 15 meters on average. It should also be noted that the military places a random error in the signals so that civilian units are not as exact in pinpointing locations as the military units.
Latitude is measured as distance from the equator, given in degrees. Think of these latitude degrees or lines as "tomato slices" of the globe. The equator is assigned the value of 0o (read as "zero degrees") latitude. The north pole is assigned the value of 90o North latitude while the south pole sits at 90o South latitude. These north and south pole values establish the extreme limits of latitude.
Latitude has been used in establishing U.S. state boundaries. For example, the line that forms the southern border of Tennessee is the 35o North latitude line, Kansas' northern border is the 40o North latitude line, and Wyoming's northern border is the 45o North latitude line--or half the distance between the equator and the north pole.
North latitude is also commonly referred to with a positive value while latitudes south of the equator are often referred with a negative value. Thus the city of New Orleans, Louisiana, could be approximated at 30o North latitude or simply + 30o latitude while the city of Durban in South Africa far south of the equator could be approximated at 30o South latitude or simply -30o latitude.
Longitude is measured as distance east or west from an imaginary line drawn from the north pole to the south through Greenwich, England (the home of the person who made up the system of longitude), given in degrees. Think of these degrees or lines like "orange quarters" of the globe. There are 180o (read as "one hundred eighty degrees") in either direction--east or west--of the line through Greenwich. At 180o the east and west longitude lines merge in the Pacific Ocean, forming another well-known line called the international date line.
Longitude lines have also been used in establishing U.S. state boundaries. For example, the western border of Nevada north of Carson City is the 120o West longitude line. The 94o West longitude line cuts right through Daviess County so all longitudes in the county will be very close to 94o West longitude.
Like latitude, longitude can be referred to with a positive or negative value instead of east or west. If longitude is positive, it is a place east of Greenwich; if longitude is negative, it is a place west of Greenwich. Therefore, all longitudes in the U.S. are west, or negative, longitudes.
By converging a latitude line (a horizonal line) with a longitude line (a vertical line), a unique and precise spot on the globe is located. Both latitudes and longitudes are further broken down into minutes and seconds. Each degree has from 0 to a maximum of 59 minutes and each minute has from 0 to a maximum of 59 seconds.
Some use UTM (Universal Transverse Mercator) readings which is a grid coordinate system that gives you a position in specific zones. The GPS Device is a machine that sends and receives signals to and from the satellites in an effort to determine your current position. GPS devices were long used by boats and airplanes, but the technology has become so affordable, that consumers can now buy them for personal use.
For Additional Information, please visit the following online GPS Tutorials:
- All About GPS
An animated tutorial on the basics of GPS from Trimble Navigation. The site also includes information on how Differential GPS works and the application of GPS to free flight avionics navigation.
The application of the GPS to a cemetery appears to be somewhat unique, though it differs very little from other consumer applications. By using a GPS device, you can stand in the middle of a cemetery, and it will determine the latitude and longitude coordinates, and even altitude if it has enough satellites tracked. It can store up to 500 locations in memory so that you can refer back to it later on.
A sample listing for the Crosier Cemetery located in South Harbor, Minnesota would look like this:
Global Positioning System (GPS) Latitude/Longitude:
46.07889 / -93.65333
A good example of the use of determining the boundaries of a cemetery can be found at the Jewish Cemetery in Rozhnyatov website located at:
Additional information on this subject can be found at:
- Using A GPS Device
Steve Paul Johnson
- Lost? Get A GPS
Elizabeth Kelley Kerstens, CGRS
- The Global Positioning System: Assessing National Policies
LOCATING GRAVES BY USE OF GROUND - PENETRATING RADAR (GPR) IMAGERY
Ground-penetrating radar (GPR) data is generated by the reflection of pulses of energy transmitted into the ground. The energy bounces off the buried features, and is detected with a receiving antenna. Each below-ground feature reflects this energy in its own unique way. Objects, and soils of different densities will generate detectable signals. By providing the user with the ability to “see” below the surface without disturbing anything, GPR is the ideal tool for locating sensitive features such as graves.
Forensic geophysical surveys employing the use of shallow ground radar imaging technology have been utilized world wide for the detection of archaeological forensic targets for nearly 20 years . Forensic geophysical surveys can locate burial sites from ancient times up to recent burials based upon the disturbance of the ground conditions. It also can be useful also to sort out the location of empty but pre-sold burial sites through the use of GPR imagery techniques. Interpretation is conducted mainly in ‘live-time’ by a geophysicist or forensic archaeologist with interim reports presented ‘live-time’ as well as full reports depending upon the cemetery’s requirements.
GPS methods are non-destructive, preserving the cemetery and the graves for future generations.
Production rates will vary according to both ground and weather conditions but under normal conditions it is possible that up to 100 graves may be examined per day.
Though GPR does not currently reveal details such as skeletons or coffins, it does show excavation features. In some cases, the actual shafts of the burial were detected, while in other cases, only the near-surface soil truncation was detected. By analyzing the slice-maps, it is possible to determine that some of the burials were interred on the east side of their headstone, while others were interred on the west side. Some caskets were wooden with no metal, some were lead-lined, and others contained significant metal. Furthermore, GPR was able to detect sometimes only slight void spaces caused by partial collapse of the coffin.
Additional Information and examples of use:
- Ground Penetrating Radar Ground Penetrating Radar
- rchaeo-Physics - Location of Human Burials
- Reese Family Graveyard
New Providence, Lancaster Couny, Pennsylvania
- Specialized GIS Applications to Historical Solution-finding
Normal Hill Cemetery - 5th Street Cemetery
The use of Ariel Photography in documenting the size, number of graves, location of gravestones or even the existence of a cemetery is a seldom used method that can provide some amazing results. Here are some suggestions for obtaining and working with aerials...
First, use USGS or one of the online locators to get an approximate longitude/latitude for the area you are interested in. This will make the person who finally helps you have a much easier time in telling you what is available.
Half the time if you call the county their "information" desk won't have a clue what you are talking about. When you call ask for someone in the Engineering Department; if they can't get you pointed in the right direction ask them for the Public Works, Highway Division or someone in Building. Depending on how your county is set up, one of those places is going to have the aerial photographs. (In Pinellas Co FL it was Public Works section of Engineering).
Once you've finally tracked down the right department, ask them how many sets of maps they keep and what the dates on those sets. This can be VERY helpful if you are trying to locate a "lost" or overgrown cemetery. It may not show up on a 2000-2002 aerial, but if your county keeps dated sets, you may want the OLDEST set they have--your target may not have been overgrown then.
By looking at a series of aerial photos taken over a 20-30 year span of the same area, starting with the oldest and progressing to the newest, you might also see how someone else has encroached onto a cemetery or even devoured one either by slow encroachment or a "permitted" building project. In most cases you should be allowed to view the available maps and pick out any or all you wish to have copies made of. The copies are NOT that expensive to obtain--the high cost was in the original which your tax dollars already paid for.
Another hint that might come in handy is if some major project has been built in an area where you believe they may have removed or disturbed a cemetery, or is in the planning stages of being built, ask if it is possible to see the county permit submittals for the project (not the permit itself, but the information that was submitted to OBTAIN the permit for the project). In most states, these documents are public records and though the worker might be unwilling to show you the file, you often have the legal right to see it. Ask for a supervisor if your state law says you have a right to view public records and you are refused.
In most states they are also required to allow you copies of said plans or portions thereof for a nominal copying fee. These plans as submitted by the project engineer almost always contain an aerial photograph and design drawings providing information sometimes not provided to the public regarding the project (like that their parking lot is going to cover the old county poor house burial ground...)
One more quick tip on aerials--sometimes counties "purge" their extra copies and donate these sets to libraries. Check with the local history section of your public library--they may just have some dusty old books or rolls of old aerials stuffed away in a corner.
Acknowledgments: The above information provided by Susie Martin-Rott and published on the Old Bones CEMETERY-L Mailing List
For additional information:
- Aerial Photography Field Office Home Page
- AERIAL PHOTOGRAPHY & SATELLITE IMAGERY
- Satellite Photos, Aerial Photography, and Images
- Aerial Photography and Remote Sensing
- A Guide to archiving Aerial Photography and Remote Sensing Data
- Aerial Photograph Examples
National Aerial Photography Program (NAPP) and National
High Altitude Photography (NHAP)
- Aerial Photography of the United States and Caribbean
- Aerial Photography at UCB
- Microsoft's TerraServer
This service is a wonderful resource for locating cemeteries.