Cartographic Representation - A Primer of GIS: Fundamental Geographic and Cartographic Concepts - page 217

What is the name and or type of your feature?
What are its UTM coordinates?
With your straightedge, or paper-strip, measure the distance of this feature to
three other features:
Distance (in meters) to nearest road intersection
Distance (in meters) to highest elevation point
Distance (in meters) to nearest township/range corner
1. How large (in page units) is the feature you measured from? How will its size,
especially in comparison to the distances you measured, affect the accuracy
of your measurements? Will they be more significant than generalization
effects?
2. Do you recognize any generalization effects in the smaller scale map? Con-
sidering all five types of operations, which ones? Describe or sketch exam-
ples.
A number of grids are available for you to use in this step. Take one of the1:24,000
Scale Grids and one 1:250,000 Scale Half Mile Grid sheet. Each cell of the 1:24,000
Scale Grid is 660 × 660 feet, or 435,600 square feet (equivalent to 10 acres). For our
purposes, on the 1:250,000 Scale Half Mile Grid, each cell (approximately 1/8”) is
equal to the same length and area.
Determine the areas of some topographic features using the two following tech-
niques. If a portion of a feature fully fills a cell, it covers an area of 435,600 square
feet. Partial cells can be treated following technique A or B. You will use both tech-
niques so be sure you understand them:
A—For each cell partially occupied by the feature, estimate the proportion of
the cell that is occupied. Compute the sum of these values, then add
the sum to the area of the completely occupied cells.
B—Count the number of partial cells and multiply them by the area of an
individual cell. Then divide by 2. Next add this sum to the area of the
completely occupied cells.
To measure area, position the lower-left corner of your area grid at the lower-left
edge of the feature you will measure. Determine the areas according to technique A
or B.
Determine the size of the following areas in square feet on your 1:24,000 topo-
graphic quadrangle. If you use the “English Area Grid,” you should you use the
printed conversion factor to determine the area in acres. Otherwise, convert the num-
ber of cells using your value from Question 3 or 4.
The PLSS section your feature is located in:
Technique A