Thus, when the observation of the captain does not agree with that of the observer D, the shot is short if he extends the arm away from the target; it is also short if, D extending both arms, the shot is to the right for the captain.

SHOTS OVER AND INCLUDED IN THE ZONE FLOI.

Any shot in the angle GBH is to the left for the captain, to the right for D. D extends the arm toward the target. Any shot in the zone FLBG is to the left for the captain, in line for D. D extends both arms. Any shot in the zone HBOI is in line for the captain, to the right for D. D extends the arm toward the target.

Thus, when the observation of the captain does not agree with that of the observer D, the shot is over if he extends the arm toward the target; it is also over if, Dextending both arms, the shot is to the left for the captain.

SHOTS CLOSE TO THE TARGET.

Any shot in the quadrilateral ALBO is in line for the captain, in line for D.

Doubtful Shots.-Any shot in the angle DOI is to the right for the captain; to the right for D.

Any shot in the angle CLF is to the left for the captain; to the left for D.

To sum up: Whenever the observation of the captain does not agree with that of the observer the shot is over if the observer extends the arm toward the target; it is short if the observer extends the arm away from the target.

If the observer extends both arms, the shot is over if it is to the left for the captain; the shot is short if it is to the right for the captain.

If the observer extends both arms the shot is close to the target if it is in line for the captain.

There is no doubt if, the shot not being in line, the observation of the captain agrees with that of the observer.

CHAPTER VII

POSITION AND THE MASK

Positions are defined as masked or unmasked, according as they afford concealment or not.

When no concealment is afforded the guns are said to be in an unmasked position, and the fire is referred to as unmasked fire.

When concealment is afforded the guns are said to be in a masked position and the fire is referred to as masked fire.

The mask, then, is the intervening object which screens the guns from the view of the enemy.

If the guns are posted behind a mask in such position that the hostile position, or the target, may be seen through the sights, they are said to have sight defilade.

If they are posted where a dismounted man can just see the target over the mask, they are said to have dismounted defilade.

If where a mounted man can just see the target over the mask, to have mounted defilade.

If so that the flash of the guns will be concealed, to have flash defilade.

While the drill regulations give 12 feet below the crest of the mask as the point of flash defilade, in practice 20 feet is more satisfactory.

A mask can either be a mere screen, such as a fringe of trees, or a hedge, enabling direct laying to be employed, or it may be such a natural object as a hillside, or a dense thicket, entailing the necessity of indirect fire. In the first case the projectile passes through the mask, in the latter the tra

jectory must clear the obstacle. It would perhaps be better if concealment of the former character were strictly defined as a screen, the latter only being referred to as a mask, for the distinction is important. If fire is merely referred to as masked, we do not necessarily know whether it is direct or indirect. Therefore, we should designate the fire either as direct fire masked or indirect fire, in order to convey an exact meaning.

Practicability of the Mask.-Much has been written, and grave doubts are entertained, about the practicability of the mask in actual service. Question is raised, of course, more particularly with respect to masked fire against infantry.

In advancing against another body at a distance of some thousands of yards over ground exposed to artillery fire, infantry takes its precautions accordingly, usually assuming a formation in small groups-say from a platoon to half a dozen men. These groups, often several hundred yards apart, advance by rapid rushes of varying length. The Japanese groups are known to have advanced continuously for four hundred yards at amazing speed before lying down, a performance quite beyond the endurance of European troops in general. In view, then, of the unstationary, shifting character of the infantry as a target, much uncertainty exists, especially in the ranks of the infantry and cavalry, as to whether artillery fire is sufficiently flexible to repel an infantry assault when indirect laying is employed. While the Japanese doubt was confirmed by their experiences in the fighting around Liao Yang, we must remember that the guns there used were not comparable in efficiency with those with which the French, English, and our own artillery are now equipped.

The French system of fire against infantry seems to be more flexible than any other, because of the highly independent employment of individual guns, a single gun only being used to fire upon a small group, an appropriate target for the weapon. The danger of a less independent use of the guns in repelling

an infantry assault is the tendency of the battery commander to wait for an opening to use the four guns effectively, whereas such an opportunity may never present itself, or, if it did, it might not be until late in the action when the two infantries were in close contact. Yet indirect fire against rapidly advancing infantry does not seem to be contemplated even in the French system.

The artilleryman observing groups of approaching infantry will notice that they generally come into sight at particular points indicated by the nature of the terrain-woods, hedges, sunken roads, hills, etc.-and, further, that such of these bits of cover as form the longest salients toward him seem the most popular. "Infantry like electricity," says Major Buat, "has a tendency to escape from points.' It will also be observed that the current of groups flowing from any particular bit of cover directs itself upon another. Between the two bits of cover each group advances by short rushes; behind it are other groups, some in motion, some stationary, but all transitory.

If we now add that all these streams of groups take their origin at varying distances from the observer-for the patches are scattered irregularly over the ground-we shall have a fairly good idea of the target presented to the battery, a target more or less difficult for direct fire. "It is evident," says Major Buat, "that all the batteries in an army corps would not go far if we should try to assign one to look after every stream of groups, or even every two or three streams. Out of all the batteries thus brought into action, only a few guns at a time would be usefully employed. The rest would be firing upon unoccupied ground, or not firing at all. All this leads us to try to economize both guns and ammunition, and to use a few guns working actively instead of a large number firing slowly and intermittently. One gun should be enough to fire upon a target of a squad or two. This is practically impossible except with direct fire. Can we conceive of anything more

difficult, and more impractical, than a battalion, or a battery commander, calmly perched upon an observing station or tower, indicating the data for a large number of guns firing upon numberless small groups moving at a rapid rate, and frequently disappearing altogether? Indeed, before the data could be transmitted, and the pieces layed, new data would be required."

Based upon the foregoing considerations, and what has actually been seen at maneuvers, the principal objections urged against indirect laying are as follows:

1. The tendency of field artillery officers to seek the masked position, regardless of the tactical situation and of the end that the guns are called upon to accomplish.

2. The delay in occupying positions and in opening fire, caused by the time taken up in making preliminary reconnaissance and in computing the elements of fire.

The foregoing objections cannot be more ably answered than they have been by Colonel McMahon in a recent article to which the student is referred.*

As regards the first objection, it may be said that the excessive use of cover in maneuvers is, in the general case, caused by the fear of the artillery commander that he will be harshly criticized by the umpires for unnecessary exposures of his command, and that he will be charged up with losses which, fortunately for all those who bear arms, occur only when blank ammunition is used. The slowness may be attributed to various causes, lack of proper training of the personnel, failure to keep in proper adjustment the instruments for the conduct and observation of fire, failure to maintain proper communication between the officer conducting the fire and the firing unit, and, lastly, the tendency, which fortunately is now rapidly disappearing, to make use of coast artillery methods

*Col. John E. McMahon, G. S. C., Infantry Journal, July-August, 1911, "Concerning Masked Fire." See author's article "Concerning Masks," Field Artillery Journal, January, 1912.