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Plot a map from a land description the cheapie way.

For this exercise you will need:

a) These instructions, copies of the necessary graphs, and some graph paper. (These are available for $5 from CAVE Inc., 1/2 Fast Road, Ritner, KY 42639.)

OR - Optionally, a durable plastic circular protractor and tenths of an inch and millimeters ruler for another $2.

OR - If you are in a hurry, or a cheapskate, you can make do the first time with a schoolchild's semicircular protractor, a ruler, and any lined paper.

b) Pencil and paper.

c) Calculator. A common calculator makes the arithmetic a lot easier, though you could do it by hand if you like.

You will not need:

a) Any land,

b) Any land description,

c) Any assistant,

d) Nor to leave the comfort and safety of your kitchen.

Normally I have students plot the map using the Silva Ranger compass as the protractor. This develops familiarity with the compass and thus makes its use in the field easier. This compass costs $41 + $5 shipping & handling, which is why you will use a circular protractor for learning.

A survey station consists of some point with an individual name and location. The survey station may be located on the land, in a land description, or on a map.

Survey stations on the land or on a map are connected together with lines, similar to a "connect-the-dots" puzzle. These survey stations may or may not be at the corners of the property.

Survey stations in a land description are connected by a set of instructions telling you how to find the next station.

Look at Table 1. The station is named "0". This is the station TO which you are surveying. The station FROM which you are surveying is also named "0". The station refers to itself.

The COMPASS direction to TO from FROM is 0. A fancy name for the compass direction is AZIMUTH. The TAPE distance is also 0.

Each station must refer to either some previous station or be given some arbitrary location. Be sure that you start someplace. The best directions in the world are worthless if you don't know where to start. Have you ever asked for directions in rural America? If so, you know about directions which start at no where. Convert to now here.

Draw an arrow along one of the lines on your lined paper and write an N" near it. Turn the graph paper so that the North arrow points up.

Station 0 is plotted as a little "x" labeled "0".

Line 2 of Table 1. The station TO is named "1". The station FROM is named "0". The compass direction is 40.


To find station "1" lay the circular protractor on the map, turned so the "N" points North. Slide the protractor around until you can seethe "x" which marks station 0 through the center hole. Twist the protractor until the N-S line on the protractor aligns with the lines on the map. The 40 degree compass direction lies in the direction marked "40" on the protractor.

Make a mark on your graph at the 40 degree direction. Use a straight edge to draw a straight line from the "x" marking station 0 to and through the mark you just made marking the 40 degree direction. Now use your ruler to measure off 200 feet [at the scale of 100 feet per inch] along the 40 degree direction. That will be two full inches. Now put an "x" at this point and label it "1".

Ain't this easy?

If you can do it once, then you can do it twice. On to Line 3 of Table 1. The TO station is 2. The FROM station is 1. The way to get to TO from FROM is to go in a COMPASS direction of 122 degrees from North for a TAPE distance of 170 feet.

Put your circular protractor on the map with the "N" end pointing the same way as the North Arrow in the map. Slide it until you can see station 1 through the peephole. Precisely align the N-S line on the protractor with the lines on the map, and place the center of the protractor precisely over the station. Mark the map along the 122 degree direction. Remove your protractor and draw a straight line along the 122 degree direction. Measure off 170 feet with the 100 feet per inch ruler and mark the station. Label it "2". This is easier done than said. On to line 4.

These are the instructions to locate station 3. Plot and label station 3.

Hopefully this is still easy. If you can do it thrice, then you can do it forever. Or however long it takes to get the job done.

Plot line 5. Station 4 should be at the same place as station 0. Or at least too close to call them different. If there is more than about 20 feet (that's really 20 hundredths of an inch) between them, try it again.

If you have already tried it again, then give it up for a few days. You have blundered. Your blunder should be obvious in hindsight.

The closure error is the distance on the map between two stations which are supposed to be in the same place. It is a check on the precision of your work, and by implication, its accuracy.

Precision is like getting all the bullets in the same hole while target shooting. You have a steady hand, or a good shooting rest. Accuracy is getting them onto the proper target and evenly distributed around bulls eye. Your rifle is properly sighted in.

The closure error is best thought of as a percentage of the run. The run is the distance which you have surveyed around a loop until you used the same station location again for a closing station. Just add up all the tape distances. The run for the map of the land description in Table 1 is 865 feet.

Measure the distance between station 0 and station 4 on your map. Divide this by 865 and push the % key. If you have no distance between the stations, then you have 0.0% closure error. Congratulations.

Now, a real parcel of land

Table 2 is the land description of a real parcel of land in Kentucky. The compass is recorded in quadrants and the distance is in poles. This is the common notation in Kentucky. It keeps the landowners stupid.

The best way to handle the odd ball units of measure is to convert the the familiar common units. Change the quadrant notation to the 360 degree notation and understand where you are going.

What the quadrant notation means is to face the first direction. Then turn the given number of degrees towards the second direction. You can plot this with a semicircular school child's protractor, but that won't teach you how to survey land.

Look at Table 2, Line 2. The COMPASS direction is S72E. What this means is to face South, then turn 72 degrees towards the East.

Look at your circular protractor. South is 180 degrees. Now count off 72 degrees around towards the east. You will wind up at 108 if you do it correctly. If you have your calculator, or are old enough to be able to subtract with a pencil, then you can simply subtract 72 from 180 and get that 108.

To translate quadrants to degrees, use the following rules:

If the compass direction is a cardinal direction (N, E, S, or W), then translate to ([0 or 360], 90, 180, or 270).

If a direction is within a quadrant, then do the following with the number of degrees within the quadrant:

If the quadrant is NE, then add the degrees to 0.

If the quadrant is SE, then subtract the degrees from 180.

If the quadrant is SW, then add the degrees to 180.

If the quadrant is NW, then subtract the degrees from 360.

To translate your normal compass direction (azimuth) into the quadrant system, use the following rules:

If the direction is a cardinal direction ([0 or 360], 90, 180, or 270) then translate to (N, E, S, or W).

If the compass direction is greater than 0 and less than 90, then the degrees are correct and the quadrant is NE.

If the compass direction is greater than 90 and less than 180, then subtract the degrees from 180, and the quadrant is SE.

If the compass direction is greater than 180 and less than 270, then subtract 180 from the degrees, and the quadrant is SW.

If the compass direction is greater than 270 and less than 360, then subtract the degrees from 360, and the quadrant is NW.

Believe me, the quadrant system made a lot of sense in Antiquity (B. C., Before Calculators) when the arithmetic was done by hand. Its only use today is to confuse those who would survey land themselves.

A pole is the same as a rod, is the same as a perch.

Still confused? That's 16.5 feet in the English system of measurement.

To plot a map at the scale of 100 poles to the inch, you could make a new ruler labeled so that each tenth of an inch equals 10 poles. Each inch is 100 poles. Or you can use your old 100 feet per inch ruler and mentally change the scale from feet to poles.

Typical Kentucky land corners are identified under comments.

Translate the compass directions and plot a map of this property. Plot it on the same graph paper as you used before.

Draw a North Arrow pointing towards the top of the paper. Note the scale; "100 poles per inch". Start where I have marked an "x" and labeled it "10".

When I plotted a map of the data of Table 2, I really couldn't see any closure error. Calculating with a hand calculator, I determined the closure error to be 3.0 poles, or 0.4%. The direction to station 0 from station 4 is 293 degrees. Compare this with the closure error of your plot. Remember, the percent closure error is the map measured distance between the two stations representing the same location on the ground, divided by the run around the surveyed loop, times 100%. You should come out with a closure error of less than 2%. Anything more is blunder.


A bit more about blunder and error. Error is a small difference of opinion which sneaks into measurements. This is due to the unfortunate fact that the real world isn't mathematically perfect.

Error is a part of this method, as it is with all real measurements. So far you have made errors in placing the exact center of the protractor over the station, in aligning the protractor with the lines on the graph paper, in getting the mark exactly at the proper degree, in placing the straightedge so that the direction line goes exactly through the from station and the direction mark, in placing your distance ruler with 0 exactly over the station, in guesstimating where some distance such as 293 3/4 really is on the ruler, and in getting the station mark exactly where you want it. And the protractor and ruler have error in their manufacture. Plus a few more errors that I haven't thought of yet.

Can't eliminate all errors

You can never eliminate all the errors. Just realize that they are there, and manage them.

Blunders are the big mistakes. The most common blunder in surveying is to read the wrong end of the compass. You are going just exactly bassackwards from where you think you are going.

Blunders are obvious when you notice them. When eliminated, they are gone completely. Except that friends keep reminding you of

the time when you surveyed for half a day before realizing that your compass was always pointing toward your new belt axe!

Blunders, by definition, are big enough to catch and cure. Always be sure that your work has built-in blunder traps. When they are not caught, little blunders become big errors.

More practice

Table 3 gives you some more practice in plotting a map. Note that the direction and distance units vary. Translate all of this into degrees and feet. Plot a map from this land description.


What sort of closure error did you get? What is this in terms of percent closure error? Is this an acceptable closure error? The actual calculated closure error is 0.00%. Station 33 was supposed to be the closing station as I produced these data. The distance for station 34 is my closure error when hand plotting the map. My hand plotting error was 0.8 %, which I consider to be excessive. That's why I use a computer. And the computer is easier too.

Take another look at your map. The closure error should be quite small. Now look at the boundary of the parcel and think about it. Is it possible to make a blunder and still have a small closure error? Possible, but not probable.

You're ready to plot a map

You are now ready to plot a map of whatever interests you. You may need to translate the land description into the proper format to plot. Some units of distance which you may encounter are: a pole or a perch or a rod, 16.5 feet; a rope, 20 feet; a chain, 66 feet; a link, (a hundredth chain) 0.66 feet; a furlong, (ten chains) 660 feet; a yard, 3.00 feet; a meter, 3.28 feet; la vara, 2.78 feet (Texas, variable).

If your map comes out too tiny, or if it won't fit on the paper, then you will have to change the scale of your map. A square plot containing 10 acres has the length of each side exactly one furlong, or 660 feet. At a scale of 100 feet per inch, the map of that 10 acre square would be 6.6 inches square. This fits nicely on the graph paper. You might want to plot on a few different scales just to see what happens. If you run off the graph paper, you can add another piece to that side. Line up the grid lines. Mark how the two sheets connect, or tape them together.

You can obtain a copy of the deed for a parcel of land by visiting your Recorder of Deeds, or whatever title s/ he holds in your county. Just walk into the courthouse and ask for deeds.

You will need help finding what you want, so ask. The deeds are indexed in various ways, depending upon where you are. In Wayne County Kentucky, deeds are indexed alphabetically by date. Really! I said you would need help!

To actually survey land, you will need different instruments. The protractor will be replaced with a compass. I use the Silva Ranger type 15 compass for all of my surveying work. It is reasonably cheap ($41 + $5 shipping & handling), precise to about one degree (the same as your hand plots), fits in your pocket, and is nearly indestructible. Anyone can quickly learn to take good compass directions with it.

You may already have a compass sufficient to survey it yourself. The Brunton pocket transit is also known as the Army Artillery compass. These are commonly available in Army surplus stores, after having been dropped by an excited soldier. They can be rebuilt for approximately $50. They are slower, more difficult to use, much more delicate, and more expensive than the Silva Ranger, but if you have it, use it.

A lensatic compass, also known as an Army marching compass, is not sufficient. This fine product of the American military-industrial complex was diabolically engineered. Without eight weeks of basic training in the use of the bassackwards scale, you are sure to get lost with it. Should The Enemy attempt to use one of these marching compasses, he would immediately become completely disoriented. He couldn't even find his way back from the latrine with it. Leave your lensatic marching compass in the latrine where it belongs.

A Boy Scout compass, a car compass, a "survival knife" compass, or other such compasses are not capable of being read to a sufficient precision. There are several other types of compasses which are capable of a one degree precision. If you think that you might have one of these, ask.

The ruler will be replaced by a tape measure. A 200 foot fiberglass and PVC surveyor's tape costs $28 + $5 shipping & handling. You can get away with using a carpenter's tape measure if you are careful not to snag or step on it. It's nice to get more than 12 feet in a shot, too! A steel tape will work until somebody steps on it. And you might not want to be holding on to the end of a 200 foot lightning rod.

If you have any questions, problems, or comments, write or call me. Dave Beiter, CAVE Inc., 1/2 Fast Road, Ritner KY 42639; ph. 606/376-3137; MCI Mail: 635-1762 byter@mcimail.comX.400 (Be sure to include your name in the text.)
COPYRIGHT 1995 Countryside Publications Ltd.
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Author:Beiter, Dave
Publication:Countryside & Small Stock Journal
Date:Nov 1, 1995
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