26. Scope

a. This chapter explains the map identifications and other marginal data appearing on topographic maps prepared for use by the Department of the Army.

b. These marginal items are illustrated in the charts which appear in appendix III. They are--

Chart 1--large-scale and 1:100,000 scale maps.

Chart 2--medium-scale (except 1:100, 000) maps.

Chart 3--1:1,000,000 scale maps.

c. The arrangement of marginal items will vary. For example, on sheets having a narrow east-west neatline dimension, certain items will appear in the right-hand margin rather than in the lower margin. The composition is generally the same for maps of like scales.

d. Detailed information on marginal data will be found in AMS technical manuals and style sheets published under the direction of the Chief of Engineers.

27. Map Identifications

a. Purpose. Map identifications are those items appearing in the margins of maps which serve to identify any individual map completely. On maps prepared for the Department of the Army, these identifications are the series name and scale, the series number, the edition number, the sheet name, the sheet number, the unit imprint, and the geographic location name.

b. Series Name and Scale. A map series, which normally consists of a common scale of maps which collectively cover a specific area, is generally assigned the geographic or political name of the area covered. The map scale is written as a ratio of map distance to ground distance. Example: GERMANY 1:25,000.

c. Series Number. The series number is a comprehensive reference composed of four and sometimes five elements, usually four numerals or a letter and three numerals. The number is unique for the series. It identifies the area and scale of the series. Example: M841.

d. Edition Number. The edition number is a specific identification based on the publication sequence of a particular map. Edition numbers run consecutively; thus, it can be assumed that a map labeled with a higher edition number contains more recent information than another printing with a lower edition number. The edition number also identifies the agency which produced the map. Example: Edition 4-AMS.

e. Sheet Name. Generally, a map is named after its outstanding cultural or geographic feature. The name of a cultural feature is customarily chosen, but if a geographic feature is better known than any cultural feature appearing on the map, the geographic name is chosen. Example: FORT KNOX.

f. Sheet Number. Sheet numbers for large-scale maps are based on an arbitrary geographic coordinate system covering the area to be mapped. The sheet number of a 1:25,000 scale sheet is directly related to the number of a 1:50, 000 scale sheet covering the same area, which in turn is directly related to the sheet number of a 1:100,000 scale sheet covering the same area. Sheet numbers for 1:250,000 and 1:1,000, 000 scale maps are based on the International Map of the World (IMW) numbering system. Examples: 1:25,000--6123 III NW; 1:50,000--6123 III; 1:100,000--6123 ; 1:250,000--NJ 16-4 ; 1:1,000,000--NJ 16.

g. Unit Imprint. The unit imprint is the signature of the agency responsible for printing the map. This is followed by the date identifying the particular printing. Example: Printed by Army Map Service, Corps of Engineers, 7-60.

h. Geographic Location Name. The geographic location name indicates the country, state, or general geographic area within which the map lies. The geographic location name includes the sheet name, which is repeated in the lower margin. Large-scale maps of the United States which cover an area entirely within one county or parish, carry the county or parish name below the sheet name and geographic location name. Example: FUJI--SAN, JAPAN.

i. Refer to Note. In the upper right corner of the map margin, the sheet number and series number are grouped under a note, REFER TO THIS MAP AS. This group provides the primary identification for ordering copies of a map.



j. Identification Panels. For quick identification of maps when filed or stacked, identification panels in opposite corners of the map sheet, outside the printed limits of other marginal information, are provided. These panels contain the series number, sheet number, and edition number.



28. Other Marginal Data

In addition to the identifications described above, the margin of a map contains other information important to the user in evaluating and interpreting the map (table I).

a. Credit Note. The credit note aids in evaluating the map and contains interpretive information. The note describes the method of preparation, identifies the source material used in compilation, gives the dates of aerial photography, and lists the source of horizontal and vertical control. It notes whether the map conforms with national map accuracy requirements and whether the map has been field checked. It includes any special information pertinent to the particular sheet.

b. Symbol Legend. The symbol legend defines and illustrates the symbols most commonly used such as populated places, roads, and rail roads. It also contains symbols for items peculiar to the area being mapped.

c. Index to Adjoining Sheets. The index to adjoining sheets, or on 1:250,000 scale maps the location diagram, identifies the surrounding sheets.

d. Index to Boundaries. The index to boundaries identifies the political areas appearing in the body of the map. The boundaries in the diagram are schematic but serve as aids in locating the boundaries on the map. On the 1:250,000 scale maps this information is shown in the location diagram.

e. Coverage Diagram. The coverage diagram, shown on large-scale maps, portrays in graphic form the methods of compilation, notes the dates of any photography used, and identifies and evaluates any maps used as bases.

f. Reliability Diagram. The reliability diagram, shown on medium-and small-scale maps, contains graphic references to the reliability of the sources used and identifies the scale, method of survey, and date of the basic sources.

g. Datum Notes. The horizontal, vertical, and hydrographic datum notes identify the controls used for these items on the map. Generally, horizontal and hydrographic datum notes are not shown on medium-and small-scale maps.

h. Grid Notes and Data. Maps of 1:1,000,000 and larger scale contain grid notes and a grid reference box with sample reference, to explain the grid data on the map. Maps carrying 1,000-unit-interval grid lines also show a declination diagram and a protractor scale in the margin. The declination diagram shows the relationship bet wee n true north, magnetic north, and grid north for the major grid at the center of the sheet. Maps carrying 10,000-unit-interval grid lines show a magnetic declination note. This note indicates the variation in the east and west map edges. It also shows the mean annual change.

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