Manual of Military Training / Second, Revised Edition

by James A. Moss

[1447a]. Finger System. (Used with indistinct or invisible targets and to define sectors.)

(By one "Finger" we mean the amount of frontage that one finger, held vertically, will cover, the arm being extended horizontally to its full length. In the average case this amount of frontage covered is about 1/20 of the range. For instance, at a range of 1000 yards, one "Finger" will cover fifty yards of the sector The same result will be obtained by using the rear-sight leaf in the position of aiming.)

Fig. 54

System	Example
1. Announce direction to reference point as in the vertical clock face system.	"To our right front, at 1000 yards."
2. Announce reference point.	"A stone house with two chimneys."
3. Announce angular distance and direction from the reference point to the target.	"Four o'clock, three fingers."
4. Announce range.	"Range 1000."
5. Announce objective.	"A skirmish line alongside of the fence, length about two fingers, right at the dark bush."

Fig. 55

Procedure:

The reference point is found as explained, and the vertical o'clock line upon which the target will be found. The soldiers who do not see the target will extend the aim to its full extent palm of the hand upward, finger held vertically with one side of the hand "against" the reference point. The target will be found on the four o'clock line, and touching the third finger, at 1000 yards distance, its right flank at the bush and its left flank about 100 yards farther to the right.

The following case will illustrate more concretely the use of the "Finger" system: