point of origin. For example, for the bulliondepository at Fort Knox, Kentucky, the coordinates ofthe lo-meter square in which the depository is locatedare casting 590,990 meters, northing 4,193,150meters; however, since the grid zone-row designationpins the coordinate down to a relatively small areasome of the digits of the coordinates are often omitted.Consider, for example, the part of a map shown infigure 9-16. The grid squares on this map measure1,000 meters on each side. Note that the casting gridlines are identified by printed coordinates in whichonly the principal digits are shown, and of these, eventhe initial number 5 is in small type. The understoodvalue of the number 589 is 589,000 meters. In settingdown the coordinate for this line, even the 5 should beomitted and only the 89 written down.Similarly, in expressing the grid location of apoint, some of the digits of the coordinates are oftenFigure 9-16.-Portion of a military map.9-16