Chapter V: Visual Training and Ranging

Section =33=.--General Remarks on Visual Training.[15]

=1. Importance of Visual Training.=--Great as is the loss of fire effect due to errors in judging distance and sighting, an even greater amount of ammunition will be expended without good results unless the soldier is trained to discern and select targets at close ranges, and to recognize targets described to him at longer ranges.

=2.= Even at close range, in the open, service targets consisting of troops are often impossible to discern with the naked eye when motionless if their background harmonizes with their uniform. At all ranges, except short distances within close range, troops in neutral-tinted uniform, adopting formations which allow full use to be made of ground and cover, are usually difficult to discern with the naked eye even when in motion.

=3.= Finally, targets which consist of ground or its natural features are not easy to recognize unless the eye of the soldier is specially trained for this work, upon which fire effect in battle beyond close range will depend. The eyesight of the soldier must, therefore, be developed in special powers to enable him to discern and recognize the targets of the modern battlefield at all ranges before he is able to fire at them effectively.

=4. Scope of Training.=--(i) Visual training will include discernment of targets, study and description of ground, recognition of and aiming at targets described by word of mouth, judging distance by eye, and, when possible, observation of the results of fire. Visual training should at first be separated from training in judging distance, but as proficiency is attained both should be combined after men have been instructed in military vocabulary and study of ground, which lays the foundation of instruction in recognition of targets. Training in observation of results of fire by watching the strike of bullets on the ground will be difficult to carry out except on dusty soil.

=5. Visual Training on Miniature Ranges.=--Directions for training men in the different subjects of instruction mentioned in the above paragraph, including observation of fire, are contained in Chapter X, Sec. 72, para. 4.

Section =34=.--Discernment of Targets.

=1. Elementary Training.=--Training will begin with questions framed to develop a man’s powers of discerning objects, _and describing accurately and shortly what he sees_. At first any ordinary objects in the vicinity of barracks will be counted, or instruction may be carried out as in the elementary stage of training in observation and memory according to the directions laid down in Sec. 45 of _Drill and Field Training_ of this series.

=2. Training on the Ground.=--Training will then be carried out on the ground. Exercises should first be carried out in good light, the recruits being allowed to stand and obtain a good field of view. Afterwards exercises should be carried out under all conditions of light, and in cloudy or misty weather, men being trained to discern and describe objects in the prone position in the open or behind cover, when their field of view will be restricted.

=3. Visibility of Distinct and Neutral Colours.=--For exercises in the field a certain number of dummy targets or fatigue-men will be placed or posted beforehand in various selected positions unknown to the class in the open, or partly behind cover, and against different backgrounds. The targets should include both the distinct bull’s-eye and service figure targets of different colours, and the fatigue-men should be dressed in uniforms of both distinct and neutral tints, with the object of showing the difference in visibility of distinct and neutral colours against the same background. Neutral-tinted targets should also be arranged against various backgrounds to show how background affects visibility, as, for example, the difference in visibility of a khaki uniform against a white wall, a sheet of water, a skyline, dark ploughland, a green field, a brown hedge.

=4. Effect of Background on Visibility.=--During these exercises opportunity will be taken by instructors to utilize the useful object-lessons they provide upon the use of ground and cover. Men should be made to note the varying visibility of objects according to their background. They should be taught that the visibility of targets naturally tends to increase the effect of fire directed at them by facilitating discernment, judging distance, and aiming, while the vulnerability of targets is decreased in proportion as they are invisible or difficult to discern. Men must, therefore, be taught to note the effect of different backgrounds upon the visibility of fatigue-men in service uniforms. When being trained in the use of ground and cover, they should learn, when possible, to avoid positions such as a skyline or a background which contrasts sharply with their uniforms, and may render them distinctly visible to the enemy [Sec. 72, para. 4 (ii)].

=5. Describing Targets.=--In all exercises men will be given a definite period of time--which may be decreased as progress is made--in which to locate and count targets. Each man should then be asked how many he has discerned. Men will in turn be asked to describe clearly and shortly the nature and position of any target they have discerned which has not already been described by a comrade. They should be taught to use military vocabulary in describing targets, and to indicate their position by the methods explained in Sec. 45. Visual training will thus lay the foundation of instruction in recognition of targets.

=6. Use of Field-Glasses.=--In the case of targets which are difficult to see, and which have not been discerned, the instructor may allow men to discern the target with the aid of field-glasses, and then make them try to discern the target with the naked eye, using natural features of the ground in the vicinity of the target to locate its position. This instruction will help to train men in the use of field-glasses and in recognition of targets.

=7. Effect of Movement on Visibility.=--Finally, fatigue-men will be employed to skirmish from cover to cover, and to perform the firing motions from behind cover, in order to show how motion catches the eye and exposes the firer’s position (Sec. 72, para. 3 [iii]).

=8. Locating an Enemy by Sound.=--Blank ammunition will be used to give practice to the ear in locating an enemy by sound.

Section =35=.--Military Vocabulary and Study of Ground.[16]

=1. Importance of Military Vocabulary.=--(i) Soldiers must be trained not only to discern, but to describe service targets of various kinds. For this purpose they must be instructed in military vocabulary. Military vocabulary comprises the technical terms applied to the organization, weapons, equipment, formations, and duties of various arms. Definitions of these technical terms are contained in the various books of this series, including _Drill and Field Training_, _Field Entrenchments_, and _First Aid_.

(ii) In this book, besides definitions of the technical terms which apply especially to musketry, a list of terms and definitions applied to natural and other features of ground and country is included on p. xxvi as being a necessary part of the military vocabulary used in the recognition and indication of targets.

=2. Need of a Standard Vocabulary.=--It is important that the military vocabulary in each unit of an army, and, if possible, in the whole army, should be uniform as to its various terms, especially in regard to the indication and description of targets. Both fire-unit commanders and men should therefore be thoroughly trained in applying a uniform military vocabulary correctly to various service targets, such as units of various arms in different formations and to the different natural and other features of ground and country.

=3. Method of Instruction.=--(i) Instruction in military vocabulary may be carried out in the following manner. In early lessons the instructor will describe in detail simple prominent features, such as part of a skyline or the line of a bank or hedge, and get each man in the class to describe in similar terms another part of the line. He will then practise them by the same method in describing more difficult and extensive features. In this way men will gradually learn the correct terms to apply to a great variety of natural features of ground. When men have learnt how to describe various features of ground in correct terms, the instructor will proceed to describe small areas of ground, the limits of which he will first clearly define.

(ii) He will describe the shape and nature of the ground, as, for instance, whether it is level, undulating or broken, and rocky, sandy, or pasture. He will then describe its various natural and artificial features, the different kinds of trees, fences, undergrowth, etc., on it, and the shape and size of the fields, with the colour of the earth or of crops growing in them. The approximate measurements of objects, roughly estimated, may also be given, as, for instance, whether they are large, small, of moderate size, tall, short, wide, or narrow. These rough measurements will often help to distinguish objects, such as trees, fields, hedges, or houses from one or more objects of a similar nature. Men will first be thoroughly practised in completing the description of ground and its features commenced by the instructor, and then, as progress is made in describing ground which is merely pointed out by the instructor without being partly described by him. Fig. 43 illustrates common features of ground which may be described in the manner outlined in these paragraphs.

=4. Study of Ground.=--It is clear that instruction in military vocabulary provides a good opportunity for training fire-unit commanders and men in the study of ground, which is of the greatest military importance. Therefore, in training men in the description of ground, instructors should also train them _to recognize all features of military importance_, such as good defensive positions, good lines of approach, good halting-places for attack, covered approaches, dead ground, obstacles, and good or dangerous cover.[17] When men have learned to recognize features of military importance, the instructor will indicate an area of ground, and question the class in turn as to what military features may be seen on it. Men must describe these military features in the correct terms, and they will thus learn an extremely important branch of military vocabulary--namely, that applied to ground--which must frequently be described to them and recognized by them as aiming points in a later stage of their training.

A. _Skyline_
B. _Hollow_
C. _Gentle slope_
D. _Steep slope_
E. _Dense cover_
F. _Crest of Hill_

=Fig. 43.=--MILITARY VOCABULARY--TERMS DESCRIBING COMMON FEATURES OF GROUND.]

=5. Studying Ground from Cover.=--As progress is made in the study of ground, the class should be made to examine the ground and to describe it from behind cover to accustom them to its appearance, as they will see it when firing from cover. This instruction will form a useful preparation for the duties of reconnaissance and scouting. When the class is sufficiently advanced, the areas of ground described will be increased gradually, and, when necessary, these areas will be divided into sectors, as described in Sec. 42, paras. 3 and 5, and each sector will be divided into foreground, middle distance, and background. Men will be trained to note the different zones of ground to which these terms are applied, and then to apply them correctly in describing ground.

=6. Committing Features of Ground to Memory.=--When men are sufficiently advanced, they may be practised in examining ground for a limited time, and then giving a correct description of its prominent features and principal military features with their backs to it. The instructor will check their description while it is being given by looking at the ground, and bring out points which may have been missed or forgotten by asking men questions. This practice will develop the extremely useful power of rapidly noting features of ground, and also of memorizing ground. The latter power will be useful in reconnaissance, scouting, and reports.

=7. Study of Ground in Strange Country.=--As the ground and its features, both natural and artificial, together with the names by which they are called, differ considerably in different countries, men should be trained in military vocabulary, the description and study of ground both before and during military operations in unfamiliar country.

Section =36=.--General Remarks on Ranging.

=1. Importance of Ranging.=--(i) Accurate ranging when firing is of vital importance, especially at distances beyond close range. Mistakes in judging distance or range-finding, and errors in sighting, cause a greater loss of fire effect than personal errors in shooting except at close range. But even within close range mistakes of more than 100 yards are not infrequently made in judging distance. _The more accurate the firing, the less will be the result if the sighting is incorrect from any cause._

(ii) The measurement of ranges will commence the moment a firing-point has been chosen. Range-taking increases in importance rapidly with every 100 yards beyond 600 yards up to 2,000 yards, at which distance troops not in a close formation are only visible when in motion, or with a very favourable background or light.

=2. Methods of Ranging.=--(i) The principal means of ranging are--(_a_) Judging distance by eye; (_b_) observation of fire; (_c_) use of instruments such as the mekometer and the one-man range-finder. There are several auxiliary methods of ranging such as back-reckoning, use of maps, information obtained from aircraft, artillery or machine-guns, sound and flash, cross-bearings, etc., which may be used occasionally or in exceptional cases.

(ii) Observation of fire, when possible, is an effective means of ranging. If uncertainty exists as to elevation, it is better to underestimate than to overestimate the range. If it is necessary to fire at ranges beyond 1,000 yards, and observation is not possible, or the situation demands that some effect should be produced, quickly combined sights may be employed. In all cases every available means should be employed to find correct ranges. _No available means of ascertaining ranges should ever be neglected, if time and opportunity allow them to be used._

=3. Reconnaissance as an Aid to Ranging.=--As already stated, range-finding will as a rule be in progress before fire is opened, and the rapid reconnaissance of any ground on which a fire-fight is likely to take place should provide information of the greatest value to company officers responsible for the direction of fire. In preparing a defensive position, there is usually ample time for ascertaining ranges, and for using range-marks (Sec. 40, para. 5) and preparing range-cards (Sec. 40, para. 1).

=4. Training of Officers and N.C.O.’s.=--As fire is controlled at longer ranges, practice in judging distance is more necessary for officers and non-commissioned officers than for the private soldier. Soldiers who show aptitude in judging short distances by eye should, however, be given training with their leaders at judging longer distances. These men may also be selected for training in the use of range-finding instruments and in the duties of observers (Sec. 42, para. 9).

=5. Reduction of Errors by Training.=--Officers and non-commissioned officers, by constant practice, will reduce their mean error in judging distance from about 20 per cent. of the correct distance to about 10 per cent., but much depends on the local conditions to which the observer is accustomed. With thorough training the mean error of private soldiers in judging distances within 800 yards should not exceed 100 yards. Special attention should be paid to men whose mean errors exceed this distance, with a view to discovering the cause and reducing the error.

=6. Effect of Strange Conditions.=--Serious errors must be expected in judging under strange conditions of ground and atmosphere. Exercises in judging distance must therefore be carried out before, as well as during, military operations in unfamiliar country.

Section =37=.--Judging Distances by Eye.

=1. Methods of Judging Distance by Eye.=--Distances may be judged by eye in the following ways: (_a_) By measuring the intervening ground with the eye in terms of some familiar unit, such as 100 yards; (_b_) by the apparent size of the object, if its size is known, or, in other words, by visual angles; (_c_) by the visibility of the object as affected by light, atmospheric effect, background, etc.

=2. Rules for Judging Distance by Eye.=--(i) The varying nature of the ground and its features, together with different conditions of light and atmosphere, affect general impressions of distance as measured by the eye by making objects look smaller or larger, and so making them seem nearer or further away from an observer than they actually are.

(ii) =Conditions which appear to Increase Distance.=--Objects will appear smaller, and therefore farther away than they are, under the following conditions:

(_a_) When objects are of the same colour or a colour which harmonizes with their background.

(_b_) On broken ground.

(_c_) When seen across a valley or undulating ground.

(_d_) In avenues, long streets, or ravines.

(_e_) When in shadow.

(_f_) When viewed in mist or failing light.

(_g_) When heat is rising from the ground.

(_h_) When seen near any other object which makes it appear smaller than it is by the effect of comparison.

(_i_) When only partially seen, as in the case of troops firing from cover.

(_j_) Troops kneeling or lying in the open seem farther away than when standing.

(iii) =Conditions which appear to Decrease Distance.=--Objects will appear larger, and therefore nearer than they are, under the following conditions:

(_a_) When both object and background are of different or contrasting colours.

(_b_) When the sun is behind the observer.

(_c_) In bright light or clear atmosphere.

(_d_) When the intervening ground is level or covered with snow.

(_e_) When seen across water or a deep chasm.

(_f_) When looking upwards or downwards.

(_g_) When the object is large, or when seen near any other object which makes it appear larger than it is by effect of comparison.

(iv) =A General Rule.=--A good general rule to remember for practical purposes is that _when a target is indistinct distance is apt to be over-estimated, and that when a target is distinct distance is apt to be under-estimated_. This general rule roughly sums up the effects and the various factors mentioned in paras. (ii) and (iii), which respectively tend to render targets less or more distinct.

=3. Judging Lateral Distance by Eye.=--The following is a rough guide for judging lateral distances running at right angles to the observer at various distances. With one eye shut and the hand at arm’s length to the front with the fingers perpendicular, the breadth of six fingers will cover 100 yards of lateral distance at a distance of 500 yards from the observer. Under the same conditions, the breadth of three fingers will cover a lateral distance of 100 yards at a distance of 1,000 yards. The breadth of two fingers will cover a lateral distance of 100 yards at 1,500 yards, and the width of the thumb will roughly cover 100 yards of lateral distance 2,000 yards away. This method may be employed for estimating the approximate length of an enemy’s column, or the extent of frontage known to be occupied by him.

=4. Method of Instruction=--(i) =Units of Distance.=--All the methods mentioned in para. 1 should be practised by officers, N.C.O.’s, and men under a variety of practical conditions, and in the prone, kneeling, and standing positions, until it is found that distances can be judged approximately from the general impression conveyed to the eye. The class will first be familiarized with short units of distance not exceeding 600 yards. _Special care will be taken to enable soldiers to recognize the distance of 600 yards, as it is the limit of individual fire._

(ii) =Figures.=--The class will at the same time study the visibility of the figure standing, kneeling, and lying at known distances. They will be required to remember the results of their observation, and be given opportunities of seeing figures in varying conditions of light, atmosphere, and background at known distances.

(iii) =Features of Ground.=--The class will next be practised in judging the distance of natural features of ground, such as folds of ground, hedges, patches of undergrowth, and other forms of cover, at various known distances. This instruction will be followed by judging the distances of fatigue-men seen at unknown distances in the different firing positions both in the open against various backgrounds and partly behind cover. The class will then be practised in judging the distance of features of ground and different forms of cover at various unknown distances. These various practices should be carried out with the class in the standing, kneeling, and prone positions.

(iv) =Reasons for Estimates.=--Each observer should be asked by the instructor to give reasons for his estimate of distance to guard against the habit of rough guessing. To train observers in the habit of taking into account every factor which will help them to judge distance, the instructor should consider and explain the effects of local conditions and other factors which affect judging the distance of each object he indicates after the class have made their estimates. Ample time should at first be allowed for judging distance, but as progress is made the time should be limited. The above exercises must include instruction in estimating lateral distances. _Rough guessing is never to be allowed._

=5. Aids to Judging Distance by Eye.=--(i) The class should be trained in various methods of assisting the eye when the distance of objects is especially difficult to estimate approximately. For example, a maximum and minimum estimate of the distance may be made, and the mean taken as correct. Half the distance from the object may be estimated with the aid, if possible, of some feature of ground, and double may be taken as correct. When the object is partly hidden in a fold of ground, or when it is of unknown size, distance from it may be estimated with the help of some object of known size, such as a natural feature of the ground or a human figure which may be near it.

(ii) Other rough methods which will assist them in judging distance approximately may be explained to the men. For instance, the foresight of the rifle _when correctly aligned_ will be approximately equal to the height of a standing figure at 400 yards. The width of an ordinary pencil held horizontally at arm’s length before the eye will cover an upright figure at 200 yards, and the lead at its thick part will cover a standing figure at 600 yards.

=6. Tests in Judging Distance by Eye=--(i) =Directions regarding Tests.=--In every company, and at depôts, in addition to instructional exercises, at least one test in judging the distances of four objects will be held for all ranks in every three months, the distances of the objects being between 200 and 800 yards.

All company officers, non-commissioned officers, and those men who are in possession of badges for judging distance, will also be tested once in every three months under regimental arrangements in judging the distances of four objects between 200 and 1,400 yards.

Brigade commanders and officers commanding districts will issue such orders as may be necessary for exempting non-commissioned officers and men from these tests, but every officer and sergeant who would command a company or smaller unit on mobilization should attend four tests annually in judging distance up to 1,400 yards.

(ii) =Conditions of Tests.=--During tests in judging distance no assistance from maps or other means should be allowed. The tests will be conducted on unfamiliar ground, half the objects consisting of fatigue-men or dummy figures representing skirmishers, and half of natural objects marking fire positions, such as would be occupied on service.

The observers will lie down or kneel behind cover, and estimates will be recorded by adjusting the sights (or in the case of officers by writing) in multiples of 50 yards; the objects should have been previously placed or selected, or the position of the observers should be chosen, so that the correct distance may closely approximate to some multiple of 50 yards.

Half a minute will be allowed for each estimate, reckoned from the moment when the object is pointed out or a shot is fired to draw attention to the position of the object. At the conclusion of the half-minute a whistle should be blown, when the observers will stand to attention, and no further adjustment of the sights or writing will be permitted. The register-keeper will then examine each rifle or paper, and record the estimates in the register. On return to barracks, the mean percentage of error of each observer will be entered in the register, which will be preserved for record.

On the completion of the classification practices, the mean percentages of error made by each individual officer, non-commissioned officer and man since the last classification will be added together and divided by the number of tests which he has attended, the average thus obtained being regarded as the standard of proficiency of the individual until the next classification.

Officers, non-commissioned officers, and men whose mean error exceeds 20 per cent., and those who have attended less than two tests, will be regarded as inefficient. Additional practice will be afforded weekly to all officers, non-commissioned officers, and men who are recorded as inefficient, until the next quarterly test. Officers and sergeants whose mean error exceeds 20 per cent. will not be classified as better than second-class shots.

Section =38=.--Range-finding by Observation of Fire.

=1. When Observation is Possible.=--Observation of results is the best means of correcting errors in sighting, but it is only practicable (_a_) when the ground in the vicinity of the objective is of a nature to show the strike of the bullets by dust, or (_b_) when the enemy is in the open, and the accuracy of fire can be judged by its effect upon him.

=2. Nature of Fire Necessary for Observation.=-_-A considerable volume of rapid and concentrated fire is necessary to enable the strike of bullets to be observed_, and for this purpose one or more Maxim guns, or not less than two platoons, should be employed to fire. The distance and nature of the ground will determine the volume of fire required, but the greater the difficulty of observation the greater must be the volume of fire. When trying for observation, third-class shots should not be permitted to fire.

=3. Method of applying Fire for Observation=--(i) =Elevation.=--An elevation well _under_ the estimated distance should first be selected, and if the fire can be observed, the elevation should be increased by not less than 100 yards at a time until the nucleus of the bullets is seen to fall on the desired spot.

(ii) =Objective.=--The point at which the fire is directed may be the actual objective, or ground in its vicinity which is more suited to observation of the strike of the bullets.

(iii) =Position for Observation.=--The best position from which to observe fire is behind, and, if possible, above the firers; but in this position the bullets which fall short will be most easily seen, and may be mistaken for the nucleus of the fire. Further, all shots will appear to strike nearer to the observer than is really the case.

(iv) =Hints for Observers.=--To an observer on or behind a flank of the firers, shots which pass over the mark will appear to fall towards the flank on which he is posted, and those which drop short to fall towards the opposite flank. Thus, if the majority of shots seem to an observer on the _right_ flank to fall to the _right_ of the mark, the range has been _over-estimated_, and if they seem to fall to the _left_, it has been _under-estimated_.

=4. Verifying Ranges by Fire.=--When there is time and opportunity for doing so, ranges which have been taken beforehand, especially those taken in preparing a defensive position, should be verified by the results of firing a number of rounds.

Section =39=.--Ranging by Auxiliary Methods and by Instruments.

=1.= Training in ranging should include instruction in practical auxiliary methods such as by maps and range-finding instruments. _Exercises in ranging by means of maps, range-finders, and the eye, used in combination, should form an essential part of the fire-direction practices of the annual course of musketry._

=2. Ranging by Map-Reading.=--Ranges may be ascertained by the use of small scale maps, though large scale maps, if available, will be better for this purpose. Instruction in field-sketching and reconnaissance affords excellent opportunities for training in judging distance. For map-reading, see _Signalling_ of this series; and for field-sketching and reconnaissance, see _Drill and Field Training_ of this series.

=3. Back-Reckoning.=--Back-reckoning may be defined as deduction as to distance made from any known range. For instance, in advancing on a position the range of which is ascertained on commencing the advance, the distance gained by each forward movement may be deducted from the original range of the position in estimating its range for firing on it at successive halts. Again, the range of an objective further away than another objective, of which the range is known, may be estimated by adding to the known range the estimated distance of the former from the latter objective. An example of back-reckoning is shown in Fig. 44.

=4. Ranging by Gun-Flash and Sound.=--Light travels at the rate of 186,000 miles a second, so that a gun-flash is practically seen as it issues from the muzzle, irrespective of the distance of the observer. Sound, on the other hand, travels about 1,100 feet, or about 365 yards, a second. By timing the interval between seeing the flash of a gun and hearing the report, its approximate distance may therefore be deduced. This, of course, will only be possible when the position of the gun is betrayed by the flash, and when guns are fired singly at appreciable intervals, or simultaneously, so that there is practically one flash and one report at a time.

=5. Range-Finding Instruments.=--A certain number of officers, N.C.O.’s, and men in each unit will be trained to use the One-Man Range-Finder or the Mekometer instrument, full directions regarding the use of which will be found in the official handbooks dealing with these instruments.

Section =40=.--Range-Cards and Range-Marks.

=1. Range-Card.=--A range-card is a device for giving ranges to various points in a field of fire for use in attack or defence. Range-cards should be prepared by fire-unit commanders for their own use and for use by N.C.O.’s and observers. When possible, the best way to prepare a range-card is to use a piece of a large scale map of the country on which to draw the range circles and direction lines. There will usually be more time for preparing range-cards in defence than in attack, and consequently range-cards prepared for defensive positions will as a rule be more elaborate than those made for use in attack.

_Note._--The distances on the left are those from the enemy’s
position. Those on the right in brackets are only for the
range-taker’s information, and should not be shown on the card to
avoid confusion.]

=2. A Simple Range-Card for Attack.=--Fig. 44 shows a rough example of a simple range-card made for use in attack over the ground shown in the left sector of the sketch in Fig. 47, from which it will be seen that the objects on the range-card are taken. This has been done to make the example more practical and interesting. The ranges are supposed to be taken from the cross-roads at X to a series of prominent objects on or a little to either side of the line of advance. The distance of each of these points _from the enemy’s position_ (2,000 yards away) is carefully noted, and thus ranging during the attack is greatly facilitated. The range of the enemy’s position from intermediate points can also be more easily estimated by back-reckoning.

_Note._--The point from which ranges are taken should always be
described clearly on the card to facilitate setting it.]

=3. A Simple Range-Card for Defence.=--Fig. 45 shows a rough example of a simple range-card made for use in defence. The ranges in this case are supposed to be taken from the point _A_ immediately south of the church. The direction line from _A_ to the church is drawn thicker than the other lines to facilitate “setting” the range-card in the same manner in which a map is set. When the card is set for the point from which ranges are taken--which is noted on the card--by pointing the thick direction line on the church, the other direction lines will indicate the ranges of the other points marked on the card.

=4. Foreground Range Sketch.=--(i)Fig. 46 shows an example of a foreground range sketch for use in a defensive position. Such a sketch would as a rule only be made in connection with very carefully prepared firing-points; but as from seven to ten hours or more is required to make any serious attempt to prepare and conceal a series of firing-points carefully, it is clear that the range-taking and range-marking party should have ample time to make an exhaustive reconnaissance of the foreground, to put out the range-marks, and to record their work in some simple form. One sketch such as Fig. 46 is sufficient for the commander of a group of firing-points.

(ii) Points, the range of which may be ascertained and marked with advantage in such sketches, include the exits and entrances to all areas of dead ground, or likely cover from view or fire; the crests or skylines--as seen from the firing-points--of all ridges and humps on the foreground; patches or lengths of road likely to be traversed by the enemy; gaps and gates in fences; corners of fields and enclosures; bridges, culverts, etc.; and conspicuous single objects, as guide-marks from which to estimate adjacent distances, such as isolated buildings, signposts, rocks, milestones, double telegraph-posts, or other such features.

(iii) As will be seen in Fig. 46, names may also be allotted to patches of dead ground within 1,000 yards or so of the firing-point. The abbreviated names of months and days of the week lend themselves to such a purpose, though any other short names will do equally well.

_Note._--Ranged points are indicated by a thick line. The
appearance of the Range-Marks is shown thus:--VIII. [= 850 yds.]
Names have been allotted to important dead spots within 1,000
yards--_e.g._, FEB. refers to the dead area immediately behind
the ridge ranged as 850.]

=5. Range-Marks.=--Range-marks are of special value to the defenders in those firing-points in which they have been told off _to watch for and deal with the enemy’s supports and reserves_ during their advance, after fire has been opened and the enemy’s firing-line is already pinned down, or is unable to cross certain areas on a foreground prepared for defence until strongly reinforced (see p. 162, para. 3 (x), _Field Entrenchments_ of this series).

=6. Marking Ranges on Ground.=--(i) The actual marking of ranges on the ground by means of visible marks may be done as follows: Range-marks should be provided, and should be placed on that side of large trees, houses, banks, etc., which is only visible to the defence. The simplest arrangement consists of one white object per 100 yards range; 500 yards may be denoted by the sign =V=, made with two boards, poles, etc.; and 1,000 yards by the sign =X=; intermediate hundreds being indicated by single objects in addition, as above described. On a bank or slope facing the firing-points Roman numerals may be cut out on the turf, etc., or formed by arranging stones or planks.

(ii) =Marking on Trees.=--For marking on a tree the hundreds marks must be one below the other, and patches of tin do very well for this. For marking “fifties” an object much smaller but distinctly visible may be added, or one object quite different to the remainder. On a tree marked with tin discs, for example, half a disc would do for 50 yards.

(iii) =Marking on Buildings.=--For marking on a building, the colour to be used depends on that of the masonry, etc. A whitewash-brush is one of the best implements, if obtainable, and the marking, can be either large Roman numerals or ordinary figures if they can be read clearly.

(iv) =Examples of Marks.=--In Fig. 46 five artificial range-marks are shown--namely, 0000·(450) at the stack, V on May hill, VII on March-April ridge, VII·(850) on Dec.-Feb. ridge, and X where Monday road disappears into Hereham village. The walls round the village might be marked in a similar manner, but the sketch is too small to show the marks.

(v) =Size of Marks.=--A practical rule for the _size_ of mark is 1 foot of height to the mark per 100 yards in the range, unless the background is very good--such as black spots on a white wall--when half this allowance will be ample.