point of origin. For example, for the bullion
depository at Fort Knox, Kentucky, the coordinates of
the lo-meter square in which the depository is located
are casting 590,990 meters, northing 4,193,150
meters; however, since the grid zone-row designation
pins the coordinate down to a relatively small area
some of the digits of the coordinates are often omitted.
Consider, for example, the part of a map shown in
figure 9-16. The grid squares on this map measure
1,000 meters on each side. Note that the casting grid
lines are identified by printed coordinates in which
only the principal digits are shown, and of these, even
the initial number 5 is in small type. The understood
value of the number 589 is 589,000 meters. In setting
down the coordinate for this line, even the 5 should be
omitted and only the 89 written down.
Similarly, in expressing the grid location of a
point, some of the digits of the coordinates are often
Figure 9-16.-Portion of a military map.
9-16
