roes 
 
SKETCHING METHODS 
 
 BY 
 
 W. C. SWEENEY 
 
 Captain 21st U. S. Infantry 
 
 The Hicks-Judd Company 
 San Francisco, Cal. 
 
Copyright, 
 By CAPT. W. C. SWEENEY, 
 SAN FRANCISCO. 
 
CONTENTS. 
 
 PAGE 
 
 Object of sketching 9 
 
 Classification of sketches . . . . 18 
 
 Outline for beginner . . . 19 
 
 Sketching tools 24 
 
 To orient the board 24 
 
 Conventional signs ..... 34 
 
 Title 43 
 
 Scales 45 
 
 What a sketch should show ... 56 
 
 Horizontal detail 57 
 
 Traversing . . . . . . 58 
 
 Intersection . . . . . .58 
 
 Resection 59 
 
 Estimation .60 
 
 Vertical detail 61 
 
 Contours . . . . . .64 
 
 Detail shown by contours ... 66 
 
 Logical contouring 69 
 
 Contour framework . . . . 71 
 
 Notes for field work .... 78 
 
 Position sketch 81 
 
 Adjustment to close .... 84 
 
 Completing sketch ..... 85 
 
 Outpost sketch . 87 
 Place sketch . . . . . .89 
 
 Road sketch 91 
 
 Reconnaissance sketches .... 98 
 
 366457 
 
INTRODUCTION. 
 
 The writer's idea in publishing Sketching 
 Methods is to simplify instruction in the 
 subject and to clear away the mathematics 
 and the mystery which seem to cling to it. 
 The average student becomes confused be- 
 cause almost always he is required to study 
 map making before he gets started on sketch- 
 ing and the result is a jumble of ideas until he 
 learns to work without instruments. When 
 he learns this he has learned to sketch. It is 
 thought that a presentation, in as condensed 
 form as possible, of the methods developed 
 by expert sketchers at the Army Service 
 Schools will be of great assistance not only to 
 students but also to instructors. The writer 
 believes that there is no necessity for teaching 
 the use of the clinometer and scale of slopes 
 in order to teach students how to contour. He 
 believes that sketching can be taught more 
 quickly and as thoroughly by direct methods 
 than by indirect ones. He has tested this belief 
 arid proved its soundness. In this time of 
 emergency it is impossible to secure com- 
 
6 INTRODUCTION 
 
 passes, pacetallys, clinometers, tripods and 
 other expensive frills that have been a part of 
 sketching for so long". Even if they could be 
 procured there would not be time to teach 
 their use, for intensive training means train- 
 ing under pressure and that means do away 
 with frills and get down to practical and direct 
 methods of instruction. 
 
 The student should be taught what scales 
 are, how to make conventional signs and their 
 meaning, how to locate points both horizon- 
 tally and vertically, how to estimate differ- 
 ences of elevation of critical points and how 
 to contour by logical methods and finally what 
 is to be shown on a sketch. He should then 
 be given an area to sketch in a limited time 
 for a definite tactical purpose. He should be 
 given several such tasks to do, being always 
 forced to work under pressure, and he will 
 rapidly develop the ability to sketch. 
 
 There is no reason why every officer and 
 non-commissioned officer should not learn to 
 sketch and to read sketches within a very 
 short time. The instructor must thoroughly 
 understand the subject. Common sense must 
 
INTRODUCTION 7 
 
 be his guide. His explanations must be clear 
 and' simple, for the average man, especially 
 one with a little service, is looking for some- 
 thing hard when you mention sketching to 
 him. A pencil, paper, and home-made ruler 
 and board are sufficient tools for the experi- 
 enced sketcher and should be enough for the 
 beginner. 
 
 W. C. SWEENEY. 
 Presidio, San Francisco, 
 May 26, 1917. 
 
MILITARY SKETCHING 
 
 OBJECT OF SKETCHING. 
 
 Military sketching is an art. Its general 
 principles may be learned from text books, 
 but the mechanical execution can no more be 
 learned from them than can the art of paint- 
 ing. The degree of proficiency attainable de- 
 pends upon the intelligence of the sketcher and 
 the amount of time given to its practice. 
 
 A map is a projection to scale of the topo- 
 graphic features of the ground. It is made 
 with exact instruments, and its accuracy and 
 completeness are the primary considerations 
 in its making. 
 
 A military sketch is a report of the topo- 
 graphic features of a section of country in 
 which certain conventional signs are used as 
 substitutes for words. Its accuracy and com- 
 pleteness are affected by the "time available," 
 the "instruments at hand/' and the "tactical 
 conditions" under which the sketcher is work- 
 ing. The difference between a map and a 
 sketch must always be in mind. 
 
10 SKETCHING METHODS 
 
 A report by means of a sketch contains in- 
 formation which it is practically impossible 
 to convey by written words. Every officer, 
 below field rank, is liable to be called upon at 
 any time to make a report on the country 
 under such conditions that only a sketch will 
 answer. All officers, especially those of field 
 and higher rank, are constantly required to 
 read maps and sketches and to make tactical 
 decisions and dispositions based upon them. 
 The ability to make a sketch guarantees the 
 ability to read and understand both maps and 
 sketches. A sketcher finds no difficulty in 
 reading a map. Ridge and valley lines are at 
 once apparent, and he reads the map easily, 
 rapidly and understandingly. A sketch is 
 more difficult to read than a map. One who 
 is himself a sketcher has greater facility in 
 reading a sketch, because he can grasp the 
 sketcher's meaning more quickly than can one 
 who has never sketched. 
 
 In any well regulated scheme of instruction 
 for military officers, military sketching occu- 
 pies an important and distinct place. The ne- 
 cessity for having junior officers skilled in this 
 
SKETCHING METHODS 11 
 
 art and the advantages accruing from the abil- 
 ity of field and higher ranking officers to read 
 sketches quickly are recognized everywhere. 
 In the field, the report by means of a sketch 
 is the rule, not the exception. 
 
 An ordinary use of a sketch may be illus- 
 trated by the following assumed situation 
 (%. 1): 
 
 Our Division is marching south, in hostile 
 country, toward an enemy who was this morn- 
 ing reported to be about twenty miles south 
 of us and moving north. Our cavalry screen 
 is four miles south of Y. Our regiment forms 
 the support of the advance guard. 
 
 The Colonel has a map of the country on 
 a scale of one inch to the mile. This map was 
 made several years ago. It shows only the 
 flat detail, houses, towns, roads, railroads, 
 stream lines, trees, etc. The undulations of 
 the country are not shown. 
 
 At a halt along the road, the Colonel calls 
 to you, and showing you his map, says : "I 
 will arrive at Y at 4.30 p. m. today with the 
 point of the advance guard. The Division will 
 camp tonight at Dover and the Advance 
 Guard (less our regiment) about l /2 mile 
 south of Dover. Our regiment will form the 
 
12 
 
 SKETCHING METHODS 
 
 Scale: l"= I mile 
 
 Fig I 
 

 SKETCHING METHODS 13 
 
 outpost on a front from X (*/ mile west of 
 Y) through Y to Z (1 mile east of Y). Take 
 four mounted orderlies and reconnoiter from 
 X to Z and far enough to the front for out- 
 post purposes and report to me at Y on my 
 arrival there. I want such a report as will 
 enable me to determine how best to dispose 
 the regiment for outpost duty without un- 
 necessary delay." 
 
 On the Colonel's map, you saw that Y is a 
 crossroad formed by the road over which the 
 Division is marching and the straight X-Z 
 road. 
 
 You arrive at Y at 1.00 p. m. You have 
 three and one-half hours in which to make 
 the reconnaissance. You must at once recog- 
 nize that only by means of a sketch can you 
 gather and convey the necessary information 
 to the Colonel. 
 
 At 4.30 p. m. you hand your sketch to the 
 Colonel at Y. Reading it, he quickly gains 
 an idea of the "lay of the land" and is able 
 to dictate his order so that his troops may be 
 marched directly to their several outpost posi- 
 ticns. 
 
 Sketches vary in the amount and value of 
 the information that they convey in exactly 
 
14 SKETCHING METHODS 
 
 the same manner as do written messages and 
 reports. The same faults are found in all. 
 
 It must always be remembered that if there 
 is plenty of time and conditions permit, the 
 commander will send his engineers or others 
 with accurate instruments to make a map of 
 the desired area. As a consequence, sketches 
 are made only when there is not time to make 
 a map or when conditions do not permit it. 
 The time required to make a sketch is always 
 a most important factor. It will usually be 
 found that the sketch is wanted for use just 
 as soon as it can be gotten, and often that 
 it is wanted in such a short time that only an 
 outline of the desired area can be made. It 
 is in such a case that the judgment, experi- 
 ence, and tactical training of the sketcher play 
 such an important part. If the sketch must be 
 slighted in some parts, he must be able to de- 
 termine what parts to slight and w r here accu- 
 racy and detail are necessary, and he cannot 
 determine this unless, knowing the object for 
 which the sketch is made, he realizes what the 
 commander needs to know about the ground. 
 
SKETCHING METHODS 15 
 
 From the foregoing considerations, certain 
 conclusions have been deduced for the guid- 
 ance of the sketchier. These may be summar- 
 ized as follows : 
 
 1. The assigned area or distance should be 
 covered in the time allotted. 
 
 2. Clearness is very important. No matter 
 how much valuable information may be 
 gathered, it will be of little use unless it 
 be clearly shown. 
 
 3. The sketch should contain all data of 
 military value to the purposes for which 
 it is needed. It may be a model in its 
 technique and yet have left out some 
 feature of such military value as to make 
 it of little or no use. 
 
 4. A sketch may be inaccurate in many of 
 its measurements and still be so clear in 
 showing what is meant and have such 
 military value, that the inaccuracies make 
 no difference. Accuracy, therefore, 
 though always to be sought, must be sub- 
 ordinate in a relative degree to finishing 
 the task in the time allotted, to clearness 
 of expression, and to military value. 
 
16 SKETCHING METHODS 
 
 The relative importance of the foregoing 
 principles may be determined in each case by 
 a careful summing up of the requirements of 
 the situation which calls for the sketch. 
 
 In the assumed situation cited, you should 
 be able to determine at once just what the 
 Colonel will want to know about the area be- 
 fore issuing his outpost order. You should, 
 therefore, know what features and distances 
 to estimate and what to measure, where to go 
 fast in your work and where slow. 
 
 Summing up the situation, you would real- 
 ize: 
 
 1. That the Colonel will need to have a 
 sketch of the whole area before him; 
 
 2. That the information contained in the 
 sketch must be so clear that there can 
 be no mistake about what is meant; 
 
 3. That all features which have value in 
 outpost duty should be especially noted; 
 for instance, a hill about three hundred 
 yards south of Y, commanding the road 
 from the enemy, can be held by com- 
 paratively few men. The strength of 
 this position must be indicated on the 
 
SKETCHING METHODS 17 
 
 sketch, as it has a direct bearing on the 
 number of men assigned to the various 
 sectors. 
 
 4. That the sketch must be as accurate as 
 possible, consistent with (1), (2), and 
 (3). 
 
 There may arise cases where the judgment 
 of the experienced sketcher will cause him to 
 change the relative value of the foregoing 
 principles. This is to be expected, because 
 each sketch is a problem in which the sketcher 
 must use his best judgment in determining 
 how to gain and to convey the desired infor- 
 mation. 
 
 The beginner, however, must learn to sketch 
 before he can pay much attention to these 
 considerations. Clearness, accuracy, and speed 
 in the order named should be his guide until 
 he has attained a fair ability in making a 
 sketch. 
 
 The habits formed in learning to sketch will 
 have a great influence upon the speed and skill 
 that may be attained. From the start, system 
 in the methods of working should be prac- 
 
18 SKETCHING METHODS 
 
 ticecl. No one can become expert at sketching 
 unless the habit of working systematically is 
 acquired. 
 
 CLASSIFICATION OF SKETCHES. 
 
 The name given usually indicates the nature 
 of the sketch. There are two general classes 
 of military sketches: (1) area sketches; (2) 
 reconnaissance sketches. 
 
 Area sketches are classified as : 
 
 1. Position sketch. This is a sketch of an 
 area to all parts of which the sketcher 
 has access. Scale usually 6 inches to the 
 mile; V. L, 10 feet. 
 
 2. Outpost sketch. In this the sketcher 
 travels along and in rear of the outpost 
 line sketching the area to the front. Scale 
 6 inches to the mile; V. L, 10 feet. 
 
 3. Place sketch. The sketcher is located "in 
 one place" on a hillside or hilltop in a 
 restricted area, from which he sketches 
 the area to the flanks as well as to the 
 front. Scale 6 inches to the mile; V . I., 
 10 feet. 
 
 Reconnaissance sketches are classified as: 
 
SKETCHING METHODS 19 
 
 1. Road sketch. This is usually made 
 mounted. The sketcher preceding the 
 column sends back his reconnaissance 
 sketches as promptly as possible, so that 
 the commander may use the information 
 contained in them on the march and in 
 making his dispositions. Scale 3 inches 
 to the mile; V. I, 20 feet. 
 
 2. River reconnaissance sketch. This is usu- 
 ally made with the idea of securing a 
 special report of topographical features 
 and other features on a river line. Many 
 of these cannot be shown by conven- 
 tional signs and are written on one side 
 of the sketch. These sketches are made 
 mounted. Scale 3 inches to the mile; 
 V. I., 20 feet. 
 
 3. Railroad reconnaissance sketch. Similar 
 to the reconnaissance of a river. Scale 
 3 inches to the mile; V. I., 20 feet. 
 
 OUTLINE FOR BEGINNER. 
 
 The following is a general outline of the 
 successive steps that may be taken in learning 
 to sketch. It is inserted here merely as a 
 
20 SKETCHING METHODS 
 
 guide to those who are taking up sketching 
 alone or in company with others who are also 
 beginners. The time available to the student 
 must be used to the greatest advantage, and 
 he alone is able to divide it with that in view. 
 For this reason, the steps are merely advisory. 
 All indoor practice suggested should be taken 
 up and carried on simultaneously with field 
 work. 
 
 In sketching, as in any other art, practice 
 only makes perfect. The steps to be taken by 
 the beginner may be analyzed as follows : 
 
 1. Study the conventional signs and prac- 
 tice same. (Page 34.) 
 
 2. Lay off a measured ground course and 
 practice striding and counting strides 
 (double paces.) (Page 27.) 
 
 3. Practice making titles for different 
 classes of sketches. (Page 43.) 
 
 4. Determine stride and construct or select 
 scale of strides for 6 inches to 1 mile 
 and paste on ruler. (Page 48.) 
 
 5. Take out board and practice orienting 
 by turning arrow to north and by back- 
 sighting. (Page 24.) 
 
SKETCHING METHODS 21 
 
 6. Practice location of points by traversing 
 and intersection. (Page 57.) 
 
 7. Practice estimating horizontal distances 
 in units of 100 yards. (Page 60.) 
 
 8. Practice estimating vertical distances in 
 units of 10 feet. (Page 63.) 
 
 9. Run a traverse for a short distance, put- 
 ting in horizontal detail only. Practice 
 locating points by traversing, intersec- 
 tion, resection and estimation. (Page 
 58.) 
 
 10. Take up study of contours and prac- 
 tice logical or mechanical contouring. 
 (Page 69.) 
 
 11. Keep up practice in making conven- 
 tional signs by drawing imaginary 
 countrysides. (Page 41.) 
 
 12. Run a traverse again as in 9. Practice 
 estimating differences in elevation be- 
 tween critical points and noting same. 
 (Page 71.) 
 
 1.3. Make two or three such traverses, prac- 
 ticing to acquire speed and method in 
 your system of working. (Page 79.) 
 
22 SKETCHING METHODS 
 
 Fill in only flat or horizontal detail but 
 be particular to locate the drainage lines. 
 Practice orienting by backsight and 
 checking each time by arrow pointing to 
 north. Put a title on each before con- 
 sidering it finished. (Page 86.) 
 
 14. Select an area *4 to l / 2 mile square and 
 make a sketch of it. Practice adjust- 
 ment to close. (Page 84.) Show all 
 drainage lines clearly. 
 
 15. Meanwhile, having practiced logical 
 contouring until you can do it intelli- 
 gently and rapidly, sketch the same 
 area again in the same manner as be- 
 fore, and in addition estimate and deter- 
 mine elevations of critical points. Now 
 take this sketch and contour it by logi- 
 cal methods. (Page 70.) Do this at 
 home or at some place from which you 
 cannot see the ground you are con- 
 touring. The idea of this is to impress 
 upon the beginner the necessity of se- 
 curing all data that may be needed for 
 contouring upon one traverse over the 
 ground. 
 
'SKETCHING METHODS 23 
 
 16. Make another sketch of the same area. 
 Fill in flat detail as you go and note 
 elevation and location of critical points. 
 When you have the drainage system 
 clearly plotted, contour the sketch on 
 the ground. Space the contours accord- 
 ing to the ground. (Page 76.) 
 
 17. Make position sketches of other areas in 
 the same manner as the last one. (Page 
 83.) Never start contouring until the 
 drainage system is "pinned down" ; the 
 big features will then be seen, and the 
 little ones will take care of themselves. 
 
 18. Make at least three outpost sketches and 
 two place sketches at 6 inches to the 
 mile and 10 feet V. I. before attempt- 
 ing to make a road sketch. (Page 87.) 
 
 19. Construct a scale of strides for 3 inches 
 to the mile and take up road sketching 
 dismounted. (Page 91.) 
 
 20. Secure a mount and make a scale read- 
 ing minutes for trot and walk. Take 
 up mounted road sketching. (Page 95.) 
 
 21. Later take up other kinds of reconnais- 
 sance sketching. (Page 98.) 
 
24 SKETCHING METHODS' 
 
 SKETCHING TOOLS. 
 
 Sketching board. The issue sketching board 
 with a compass set in a trough in one edge is a 
 good board for sketching. It has an attachment 
 on the under side for securing the tripod to it. It 
 is about 13" x 14" which allows 2 miles of 
 position sketch (6 inches to the mile) to be 
 made with enough extra space to secure the 
 paper to the board. 
 
 A home-made board of the same size made 
 of light wood about % inch thick, with holes 
 in two diagonally opposite corners for a rope 
 by which to carry it makes a very good sketch- 
 ing board. 
 
 A tripod may be used but is not necessary. 
 When instructing large classes by intensive 
 methods the compass, pace tally and tripod 
 should not be used, as it requires too much time 
 to learn their use. 
 
 TO ORIENT THE BOARD. 
 
 Having tripod and compass. Set up the tri- 
 pod with board loosely screwed on to it 
 and level by eye by moving the tripod legs. 
 Note that tripod legs are firmly set so as 
 
SKETCHING METHODS 25 
 
 not to slip easily. Free the needle by turn- 
 ing the cam and then turn the board slowly 
 around until the needle swings from side 
 to side in the trough. Let the needle set- 
 tle, turning the board so that when settled 
 the needle lies directly over the north line 
 in the bottom of the trough. Without chang- 
 ing the position of the board, reach under 
 and tighten up the screw of the tripod. Care 
 must always be taken not to turn the tripod 
 screw too tight as the threads are likely to be 
 started by rough treatment. The board is now 
 oriented. Draw a line parallel to the needle 
 on the paper and mark the north end with a 
 half arrow. This magnetic meridian line is 
 sometimes marked M. M. 
 
 Without compass and tripod. Draw a line 
 parallel to the edge of the paper and place a 
 half arrow on one end of it. Turn the board 
 around until the arrow points north and the 
 board is oriented. Use watch and sun or 
 general knowledge to determine north at first, 
 thereafter orient by backsight but check back- 
 sight orientation when necessary by the same 
 methods. 
 
26 SKETCHING METHODS 
 
 To Orient the Board by Backsight. Having 
 plotted (located and drawn in) a station and 
 arrived at a point further on, which you have 
 sighted and drawn a line to, measure off the 
 number of strides taken between the two points 
 on your line, and stick a pin in the point found. 
 This is your present position. Place your ruler 
 against the pin and along the line between the 
 two points and turn the board until the station 
 which you have just left is sighted. The board 
 is oriented. Verify this by checking arrow or 
 reading the compass needle. 
 
 All of these methods of orientation can be 
 practiced in a small space. Set up the board 
 and orient by compass. Stick a pin in your 
 assumed position and draw to a fence post or 
 any object, fifteen, twenty, or one hundred 
 feet distant. Now move over to near the fence 
 post and set up again. Orient the board by 
 arrow and then verify by a backsight orien- 
 tation on the first station. For this practice, 
 a scale of an inch to a few feet may be as- 
 sumed, and the distances measured. In this 
 case, practice may be had from one point to 
 three others and then back to the first. This 
 
SKETCHING METHODS 27 
 
 will give an opportunity to check the accuracy 
 of your orientation by seeing how well your 
 lines close. Intersection and resection methods 
 may also be practiced in this same manner. 
 
 Tally Register or Pace Tally. This instru- 
 ment is used to keep the record of the number 
 of strides (double paces) taken in measuring 
 the distance between points. It is important 
 that the number of strides be counted as ac- 
 curately as possible and for this reason, the be- 
 ginner should learn to register them auto- 
 matically, that is, without giving the act of 
 pressing the lever any attention. 
 
 With the pace tally held in the left hand, 
 finger through ring, the lever is pushed down 
 each time the right foot strikes the ground. 
 This system of recording the strides is the best 
 possible, because the left hand is free" to handle 
 the register and after practice will automatic- 
 ally or subconsciously press the lever when the 
 right foot strikes the ground which occurs 
 when the left hand reaches the forward point 
 of its swing. The more nearly automatic the 
 act of recording the strides becomes, the more 
 
 
 can the sketcher's attention be given to ob- 
 
28 SKETCHING METHODS 
 
 serving the configuration of the ground and 
 the details of the country through which he is 
 passing. 
 
 However, it is possible to get very good re- 
 sults by training men to count their strides and 
 tally every hundred strides on the edge of the 
 paper: There are various ways of counting 
 and tallying strides without a pace tally. After 
 a little practice each individual will select 
 his own way. The beginner should learn to 
 stride at a uniform gait and to register the 
 strides or to count them with the least mental 
 effort. Do not attempt to take strides of a 
 certain length but step along at a natural gait, 
 swinging the arms naturally and keeping the 
 mind off of the counting of strides or of their 
 length. When walking anywhere by yourself, 
 practice counting your strides or carry the 
 pace tally and register them. If opportunity 
 offers, do this in walking to or from your 
 office or place of business. Practice it as 
 much as possible, and you will soon find that 
 the number of strides in a given distance will 
 become more and more uniform. Until one 
 learns to stride naturally and uniformly, the 
 
SKETCHJXG METHODS 29 
 
 stride will be affected by walking with or near 
 another person. 
 
 Once in a while, a tally register will be 
 found which occasionally fails to register a 
 change of 100 strides. This can be detected 
 by a peculiar click when it happens. The fail- 
 ure is often due to the sketchers not pressing 
 the lever down far enough. The register can 
 be tested indoors by watching the face of the 
 dial while pressing the lever and tallying 
 through a couple of hundred counts. 
 
 Triangular Ruler (fig. 2). The best ruler 
 for sketching is one of triangular shape about 8 
 inches long with faces about 0.8 inch wide, 
 with both ends weighted. Such a ruler has 
 been developed at the Army Service Schools 
 and can be bought at slight expense from the 
 Book Department, Army Service Schools, Fort 
 Leavenworth, Kansas. It has on it a scale of 
 inches, one of 100 yards at 3 inches to the 
 mile, and one of 100 yards at 6 inches to the 
 mile. There is ample space left on which the 
 sketcher may paste his scale of strides for 
 sketching at 6 inches and at 3 inches to the 
 mile, as w r ell as his horse's walk and trot scale 
 
30 SKETCHING METHODS 
 
 for mounted work. A very satisfactory ruler 
 ean be made by sawing in two a piece of pine 
 or other common wood about % inch square. 
 This makes a triangular ruler which is con- 
 venient in size and shape. It should be cut 
 in 6-inch lengths and should have on it the 
 sketcher's scale of strides, a scale reading 100 
 yards at 6 and at 3 inches to the mile and an 
 inch scale reading down to a 10th of an inch. 
 
 When using the ruler for sighting an object, 
 place one of the edges against the pin in your 
 station, sight along the top edge, and pivot 
 the ruler with forefinger and thumb around 
 the pin until the desired object is in line. Then 
 draw the ray (light line) along the edge of 
 the ruler next to the pin. When sighting up 
 or down a steep slope, the sketchier may find 
 it of assistance to stick a pin vertically in each 
 end of the top edge and use them to sight by. 
 
 Pencils. A soft pencil, HB grade, or Eber- 
 hard Faber No. 2 with eraser on it, should be 
 used in learning to sketch. Harder pencils 
 will tear the paper, and their marks are so 
 difficult to see that the sketcher is likely to 
 
SKETCHING METHODS 31 
 
 strain his eyes. When sheet celluloid is used, 
 a 2H pencil is better. 
 
 A knife or a pencil sharpener should be car- 
 ried, and the pencils should always be kept 
 sharp. A piece of emery paper pinned to the 
 carrier is very valuable for putting on a fin- 
 ished point. 
 
 Eraser. A soft rubber eraser is a popular 
 article in the equipment of the beginner. The 
 Ruby, Eberhard Faber, New York, is a very 
 satisfactory one. One on the pencil will serve, 
 however, very nicely. 
 
 Paper and Thumb Tacks. All sketches 
 should be made on a tracing paper in order 
 that they may be blueprinted without the 
 necessity of tracing them. For this reason, 
 tracing paper should always be used, except 
 in the earlier practice when any variety of 
 drawing or heavy wrapping paper will do. It 
 will be found that the paper, if pinned to the 
 board by thumb tacks some time before it is 
 to be used, will bulge up and have to be re- 
 adjusted. For this reason it is well not to 
 pin your paper in position until just before 
 starting out. Extra thumb tacks should be 
 
32 SKETCHING METHODS 
 
 carried. These may be stuck on the under 
 side of the board or kept in a piece of cork 
 in the carrier. 
 
 Large Headed Pins. Several of these should 
 be stuck in the carrier or clothing where they 
 can be gotten at conveniently. They are most 
 useful in sketching. Common glass-headed pins 
 about \ l /> inches long with a head about 1-10 
 inch in diameter are best. 
 
 Carrier. This can be made of canvas or 
 heavy cloth sewed over a piece of light wood 
 or heavy cardboard, or they may be purchased 
 at the Book Department, Army Service 
 Schools (fig 3). The sketcher must have 
 every appliance in its place, when he wants to 
 use it, and the carrier offers a most conven- 
 ient place for nearly all of his tools. The 
 carrier, however, is not necessary. 
 
 Stop Watch and Note Pad for Mounted 
 Work (fig. 4). These are very convenient for 
 mounted work. The pad is divided into 
 blocks. The middle line from the bottom up 
 represents the sketcher's route by minutes and 
 quarter minutes of travel, while the horizontal 
 
SKETCHING METHODS 
 
 33 
 
 nr ^^ ..,....,.....,... ^j^ '""Ji-'-'isSi 
 
 .Wl- U1 E PX PP*'P or H c 
 
 mlffl 1,1,1 li 
 
 Bin 
 
 Fia- 2L 
 
 Fig. 3 
 
34 SKETCHING METHODS 
 
 lines to the sides represent hundreds of yards 
 off from the sketcher's route. As the horse 
 trots along the road, the sketcher jots down 
 on the pad in their proper places the various 
 features which he observes. After some min- 
 utes of travel, he dismounts, and, using these 
 notes, sketches in the road over which he has 
 passed. It is well in making notes on the pad 
 to use a blue pencil for noting water courses 
 and horizontal details and a red one for carry- 
 ing along the elevations. A pencil with red 
 at one end and blue at the other can be pur- 
 chased at any bookstore. 
 
 CONVENTIONAL SIGNS. 
 
 The conventional signs used in military 
 sketching are illustrated in Field Service Reg- 
 ulations. 
 
 In practical sketching, if it is more difficult 
 or requires more time to make the conven- 
 tional sign than it does to write what is meant, 
 the experienced sketcher will write the de- 
 scription. 
 
 A sketch is made primarily to convey cer- 
 tain information. If what is meant to be con- 
 

 
 SKETCHING METHODS 35 
 
 veyed is not clear the sketch is of no use. 
 Again, if it takes a commander too long to 
 read a sketch he will blame the sketcher, and 
 as his time will probably be valuable he may 
 not be able to take time to read it. Always 
 remember that the sketch is being made to be 
 read, that the convenience of the reader is 
 sought, not that of the sketcher, that it is use- 
 less to put a mark on the sketch unless that 
 mark has a meaning which the reader will be 
 able to make out. 
 
 It is desirable that the conventional signs 
 shall picture what they represent as nearly as 
 possible, so as to be easily interpreted ; be sim- 
 ple in construction so that they may be made 
 rapidly ; not take too much space on the sketch ; 
 and that they be so clear as to be readily un- 
 derstood and not be mistaken one for another. 
 
 Practice in rapid work has developed many 
 short cuts in making them. These convey the 
 same information with fewer pencil marks and 
 probably greater clearness (fig. 5). 
 
 It is to be noted that the cross marks on a 
 railroad, the signs indicating the different kinds 
 f fences, the marks along a road indicating 
 
36 
 
 SKETCHING METHODS 
 
 \ Cut to' / 
 
 _ JVoacL Smooth and Bar- 
 -bed Wire Fences. Cut 
 
 ,\ 
 
 T 
 
 .* A H R. 
 
 / ( \ 
 \ Wood 
 d ^ox go' 
 r tS 7 
 
 _ Road. Hedge .Fence Tele- 
 -graph. Fill." 
 
 _ Culvert. Bridge wifH 
 Dimensions . 
 
 Railroad Ki$ht of 
 Fence Ma\) Be Shown or 
 jMote Stating it is There 
 I Be Made in ~ ' 
 
 T 
 
 _ Barbed Wire Fence 
 Across Countrv) . 
 Tel. Line Off Road. 
 
 vWoods \ Area Cov/erecl by Woods 
 
 -Stream Line 0* Wide 
 ^^^^kso'waS 1 Banks 2' Deep. 
 ^^^^^^^b^d^ Scattered Trees on a\\ 
 But one Branch 
 Broken Line s no Water 
 
 ^o 
 /2> 
 
 5tone 
 
 I House 6"-] Mile 
 House 3"-lMile 
 
 Where Area is 
 Not Cultivated 
 -" Leave Blank . 
 
 CONVENTIONAL SIGNS 
 
SKETCHING METHODS 37 
 
 telegraph line and the T representing a tele- 
 graph line across country, are to be made 1 inch 
 to \ l /2 inches apart on a scale of 3 or 6 inches 
 to the mile. This is done principally for the 
 sake of clearness, though a great deal of time is 
 saved by it. It is, however, an excellent rule 
 never to put a mark on a sketch, no matter how 
 small, that is not necessary. 
 
 A culvert or bridge less than 10 feet long 
 (road length) should be represented by two 
 V's at right angles to the road with the points 
 of the Vs opposite each other. Dimensions 
 need not then be given as in a larger bridge, 
 but the material and the condition, if poor, 
 should be noted," "brick, poor," or "wood, 
 bad." 
 
 Roads are conventional signs. Try and show 
 them about 1-16 of an inch wide at 3 inches 
 to the mile and about 1-10 inch wide at scale 
 of 6 inches to the mile. The road lines should 
 stand out clear and distinct with no lines or 
 >ther conventional signs crossing the road. 
 Fence and telegraph signs are placed on the 
 gs. 
 
38 SKETCHING METHODS 
 
 A hedge fence is represented by drawing H's 
 across one of the road lines at about the same 
 intervals as fence signs. Fence and hedge 
 signs are the only marks that should ever 
 appear between the borders of a road. 
 
 Stone and wood fences, being very unusual 
 features, are noted in sketching by writing in 
 "stone" or "wood" along a line drawn to rep- 
 resent the fence, if along a road use the road 
 line, with marks indicating the limits of the 
 stone or wood fence. A marginal note is sim- 
 plest and easiest. 
 
 Signs for single trees are drawn oblong in 
 shape and about 1-10 of an inch long at 6 
 and about 1-16 inch long at 3 inches to the 
 mile. Space them sufficiently to be distinct so 
 as to blueprint readily. Do not attempt to 
 show individual trees. The sign indicates 
 trees in that locality. 
 
 Houses are represented by black blocks 
 which are made square and large enough to 
 be set in the road at the scale being used. 
 That will make the house sign about 1-10 
 inch square at 6 and 1-16 inch square at 3 
 inches to the mile. 
 
SKETCHING METHODS 39 
 
 In order to proportion the signs to the scale 
 used it is convenient to always make the lines 
 that go on or along the road about as long 
 as the road is wide. This refers to such signs 
 as a telegraph line along the road, the barbed 
 wire fence lines which make the X's on a road 
 line and the signs for cuts, fills, bridges, cul- 
 verts, etc. 
 
 A row of houses occupying a certain dis- 
 tance along a road need not be indicated in- 
 dividually, but houses signs covering the scale 
 distance occupied by them should be drawn in. 
 
 A dry watercourse should be indicated by a 
 broken line, which should be wavy so as not 
 to be mistaken for a trail sign, which is a 
 broken straight line. If there is a small town 
 along your road, do not attempt in a road 
 sketch to show the individual streets, alleys, 
 and houses, but make a town sign covering 
 the area of the town, and write in its name. 
 (See fig 1, Town of Dover.) 
 
 Where the conventional sign or written 
 words cannot be put in at the place desired 
 without excessive crowding, write a ( 1 ) at that 
 place and insert description in a marginal note 
 
40 SKETCHING METHODS 
 
 opposite a ( 1 ) on the margin. Carry these 
 marginal notes by serial numbers; on a road 
 sketch, start them at the bottom of the margin 
 and run up; on other sketches, start at the top 
 of the paper and number them down. 
 
 Break contour lines on each side of a road, 
 a conventional sign, or an abbreviation (as a 
 description of a bridge). Never run them 
 through. 
 
 It should be remembered that your sketch, 
 when finished, must be ready for blueprinting 
 copies without tracing; therefore, all signs 
 should be distinct enough for this purpose. All 
 lines should be firm and clear cut. 
 
 Anyone who has the ability to learn to read 
 and write, should be able to learn to sketch. 
 In sketching, as in writing, however, the signs 
 used have to be learned, and facility in making 
 them has to be gained before much can be 
 accomplished. Much time is wasted in the 
 field by beginners on account of the fact that 
 they have not sufficient familiarity with the 
 conventional signs and abbreviations to enable 
 them to put down the right one quickly. No 
 one should attempt to sketch until the con- 
 
SKETCHING METHODS 41 
 
 ventional signs are learned and some facility 
 in making them has been acquired. This can 
 be practiced anywhere indoors by drawing a 
 skeleton sketch of roads and stream lines and 
 filling in imaginary countrysides. Locate and 
 draw in farm houses, orchards, fences, trees, 
 woods, cuts, fills, bridges, unimproved roads, 
 railroads, etc. Form a general idea of scale 
 distances but make this practice mainly to help 
 you to learn the conventional signs so that 
 when you see something that you wish to 
 represent, you will be able to put it down with- 
 out having to stop and think how you should 
 represent it. It is splendid practice for a class 
 to have the instructor dictate to them a de- 
 scription of a countryside which the students 
 represent by conventional signs at the scale 
 ordered. The various features and objects 
 are represented according to the distance and 
 direction as given by the instructor. To stim- 
 ulate interest and note progress the papers may 
 be turned in and corrected. It is not only neces- 
 sary to know the sign when you see it, but 
 it is necessary in sketching that you be able 
 to make it quickly and easily. It should be 
 
42 SKETCHING METHODS 
 
 easier for the sketcher to make the conven- 
 tional sign than to write the words. Practice 
 of this kind will also assist in overcoming the 
 diffidence that many feel about the mechanical 
 work of drawing, as it will accustom the hand 
 and eye to working with pencil and ruler. 
 
 A familiarity with the scale distance of some 
 commonly used unit of measure is essential 
 to the sketcher for putting down distances as 
 he estimates them. All estimates of distance 
 should be made in hundreds of yards; there- 
 fore the sketcher should be able to accurately 
 lay off a hundred-yard measure to the scale 
 of the map. As all work in learning to sketch 
 will be at 6 and 3-inch scales, the beginner 
 should practice, along with the making of con- 
 ventional signs, jotting clown hundreds of 
 yards at 6 and 3 inches to the mile and inches 
 and halves and tenths of inches. This can 
 be done by dotting off these distances any time 
 or anywhere and then checking them with 
 these found on the triangular ruler. This also 
 gives an idea of what may be shown at the 
 different scales. At scale of 1 inch to the 
 mile, a heavy pencil line is about 50 yards 
 
SKETCHING METHODS 43 
 
 wide; 1-10 inch at 6 inches to the mile is about 
 30 yards ; at 3 inches to the mile, it is 60 yards 
 and at 12 inches about 15 yards. This prac- 
 tice is most important for the beginner. 
 
 TITLE. 
 
 Every completed sketch should contain a 
 title, setting forth the character of the sketch, 
 the sketcher's name and rank, the locality 
 sketched, the elate, the scale (in inches to the 
 mile), a graphic reading scale of yards and 
 the north and south line parallel to one side. 
 
 All lettering on position sketches should be 
 written so as to be read from the south edge. 
 In place sketches, it should be so located as to 
 be read from the sketcher's position with the 
 sketch oriented. In outpost sketches, the let- 
 tering is read facing toward the enemy. In 
 road sketches, the lettering should be made so 
 that it may be read by anyone following the 
 route of the sketcher with the sketch oriented! 
 
 Figure 6 illustrates the title for a position 
 sketch. In another kind of a sketch, the 
 proper name and scale is substituted. 
 
44 SKETCHING METHODS 
 
 Printed letters are so much clearer than or- 
 dinary long-hand writing that they should 
 always be used in the body of the sketch and, 
 where time permits, in marginal notes. In 
 reconnaissance sketches, there will be so many 
 marginal notes that it is usually impracticable 
 to print them, and they are therefore written 
 out in long hand. 
 
 Contour numbers should also be placed, as 
 far as possible, the same as the lettering. See 
 figures 10 and 1 1. 
 
 Time is saved, and the chances of omissions 
 avoided by blocking out on heavy cardboard 
 a completed title like the one in figure 6, and 
 
 POSITION SKETCH 
 
 Near Eas+on 
 
 By W*Smi+h,Cap+. ^ nc/ /nf. 
 May 15 1915 
 
 6" = I mile 
 Yards 
 
 IQO 20O 300 tOO 50O 6OO 7OO 8OO 
 
 Fig. 
 
SKETCHING METHODS 45 
 
 keeping it in the back part of the carrier. 
 This can be slipped under the paper on the 
 board and traced. 
 
 In a road sketch, put the title at any con- 
 venient place. In all other sketches, place it 
 so as to be read from the south edge. 
 
 Where the V. I. used is different from that 
 prescribed in the normal system of scales (page 
 62), it should be noted in the title. 
 
 SCALES. 
 
 It is usual in military work to speak of the 
 scale of a map or sketch by stating the number 
 of inches on it, which represent one mile on 
 the ground. Thus we say a certain sketch is 
 made on a scale of 3 inches to the mile, mean- 
 ing that 3 inches on the sketch represents 1 
 mile on the ground. 
 
 A scale may be expressed in three ways, 
 any one of which is sufficient to acquaint the 
 reader with it. These three ways are : 
 
 1. By expression in words and figures: 3 
 inches equals 1 mile; 6 inches equals 1 mile. 
 
 2. By what is known as the "Representative 
 Fraction." This is abbreviated as ."R. F." 
 
46 SKETCHING -METHODS 
 
 
 
 The fraction expresses map distance in its 
 numerator and corresponding ground distance 
 in its denominator. For example : the R. F. 
 of a map on a scale of. 3 inches to the mile 
 
 would be written R. F. = The numer- 
 
 21120. 
 
 ator is always reduced to unity. One (unit of 
 measure) on the map represents 21120 (of the 
 same units of measure) on the ground. The 
 scale in inches to the mile is readily found by 
 dividing the denominator, 21120, into the 
 number of inches in a mile, 63360. This scale 
 is seldom used in sketching. Its use is mainly 
 in case of making a sketch which may be con- 
 verted into some foreign unit of measure. 
 
 3. By a graphic scale. This is a line drawn 
 on the map or sketch and divided into equal 
 parts. Each of these is marked with the num- 
 ber of ground units it represents. In our serv- 
 ice it is usual to make these divisions read miles 
 and halves and quarters of miles, when ex- 
 pressing the scale graphically. This scale is 
 useful on maps which are to be increased or 
 reduced by photography on account of the fact 
 that it will always read true. 
 
SKETCHING METHODS 47 
 
 There are two other kinds of graphic scales : 
 Reading and working. The reading scale is 
 made to read some well known and commonly 
 used unit of measure, as feet, yards, etc. In 
 military sketches it is made to read yards. To 
 construct a reading scale at a scale of 6 inches 
 to 1 mile, lay off a couple of inches of length 
 and divide each inch into three parts. Each 
 part will then represent 100 yards. At that 
 scale .346 inch represents 100 yards and that 
 is as near 1-3 of an inch as it can be drawn 
 with an ordinary pencil. After dividing the 
 inches into thirds divide the left division into 
 four parts each of which will represent 25 
 yards. Mark off the main scale to read hun- 
 dreds of yards. For sketching purposes one 
 mile may be said to contain 1800 yards. At 
 scale of 6 inches to one mile 1 inch will equal 
 300 yards and 1-3 inch will equal 100 yards. 
 
 The working scale is made to read the units 
 of measure used in making the sketch. In 
 sketching this is usually strides (double pace) 
 for dismounted work and minutes of travel 
 of horse at trot and walk for mounted work. 
 The completed military sketch should contain 
 
48 SKETCHING METHODS 
 
 the scale expressed in words and figures, as 6 
 inches=l mile and a reading scale to read 
 hundreds of yards. The working scale should 
 not appear on the sketch. 
 
 It is not essential that the sketcher should 
 have to do the mechanical drawing in con- 
 nection with the construction of his working 
 scale. He should know how to do it in case 
 of need. Scales for any length of stride or 
 minute scales for a horse at trot and walk 
 at any desired scale can be secured from the 
 Book Department, Army Service Schools, at 
 Fort Leavenworth. 
 
 Stride scales for 6 inches to 1 mile are 
 printed in figure 7. They are placed here for 
 convenience. To use one of them the sketcher 
 must first carefully determine the length of 
 his stride and either cut out the scale 
 for his length of stride or lay off the 
 divisions on another paper and paste on his 
 ruler. Assume that the average number of 
 strides taken by the sketcher over a one mile 
 measured course is 1048. To determine the 
 length of stride divide 63360 (the number of 
 inches in one mile) by 1048 and the quotient 
 
Fig. 7 
 
 1 2 3 
 
 i - 1 - 1 
 
 SCALE OF STRIDES 
 6" = 1 MILE 
 
 eo INCH STRIDES 
 
 1 1 1 1 1 1 1 I I 1 1 1 1 I I 1 1 i I 1 1 1 1 1 1 1 1 1 1 1 1 [ I I 1 1 1 1 1 1 1 I 
 
 U 61 INCH STRIDES ^ ^ 
 
 1 I I I I | I I I I | I I I I | I I I I I I I I I | I I I I [ I I I I | I I I I | I I I I | I I I I | I M I | I I M | I 
 
 62 INCH STRIDES 2 4 6 
 
 IJ i I I f M I I j I i I I | I I I I I I I | | | | | j | I | | | | | | | | | | | | | I | I I I I I I I I I | I I 1 I I 
 
 " 63 INCH STRIDES 2 4k 6 
 
 M-l i I ' I I i I | M I 1 j i i ! | ! I I 1 | | | I | I j I I I I | I 1 I I | I I I I | I I I I | I , I I | M i I 
 
 $ 64 INCH STRIDES 2 4 
 
 1 i 1 M | M I.I | M I I | I I 1 IjJ I I I | I I M | I MM I Mil I I I I |M M | I I I I U-i 
 65 INCH STRIDES ^ 4: 
 
 ji I M |il H j Ml I [III I Jill I | MM I Mi |MII I III II Ml 111 II INI 
 
 n <> A 
 
 66 INCH STRIDES * 
 
 |M M | Ml 1 I M ! I |l I I I M M I ! ! I 1 I II I II Ml Ml MMI I Ml | III I M 
 
 . ! 
 
 u 67 INCH STRIDES 
 
 Ml i I | I I I I | I I I I | I I I Ml I I I | I I I I [I I I I M I Ml I I li-LLI I I [ I I I I i 
 ft 68 INCH STRIDES ^ 4t 
 
 I I I I I [ i I M | I I I I | I I I I I I I I I | I I I I I I I I I | I I I M I I I I | I I I I | .l.. 
 
 ^ CQ I M /~ u C -r r% 1 1-, cr o " ^ 
 
 M I i | I I I I | I I I I | M I I | I I I I } I I I I | I I 1 I | I I i I | I i I I | i 1 i 
 70 INCH STRIDES 2 4 
 
50 SKETCHING METHODS 
 
 60.4 will be the number of inches in one stride. 
 Select the scale reading nearest to the length 
 found, in this case 60 inches would be taken 
 as the stride. 
 
 Scales constructed by the student should be 
 made in ink and, when dry, pasted on to the 
 ruler and later given a coat of shellac to make 
 them water proof. 
 
 It is very important that the sketcher de- 
 velop a uniform stride and that the strides 
 be accurately counted. To accomplish this is 
 the most difficult part of scale making. The 
 average number of strides over a given dis- 
 tance must be fairly uniform, or the working 
 scale, no matter how accurately constructed, 
 will not be of much use. 
 
 Every sketcher must have a working scale, 
 constructed to read strides, at 6 inches to the 
 mile. Later, one at 3 inches to the mile for 
 practice in road sketching should be made, and 
 when mounted work is taken up, a scale read- 
 ing minutes and fractions of minutes of travel . 
 of the horse at trot and walk at 3 inches to 
 the mile will be needed. 
 
SKETCHING METHODS 51 
 
 The making of a scale for working purposes 
 is simple and easy enough if it be kept clearly 
 in mind that it is merely a determination ot 
 the length that will be required to show a 
 given number (usually 100) of strides on the 
 ground at the scale desired. 
 
 To make a working scale of strides at 6 
 inches to the mile, measure off with chain or 
 tape a ground course along a road or prefer- 
 ably across country "over hill and dale" ol 
 one mile, three-quarters of a mile, or one-half 
 of a mile. The longer the course, the better. 
 It should be over average ground (up and 
 down hill) similar to that which is to be 
 sketched and should be carefully measured. 
 
 Walk this course both ways several times, 
 counting strides with the tally register as de- 
 scribed under "Tally Register," or by counting 
 and tallying every 100 strides with paper and 
 pencil. Do this on different days and at dif- 
 ferent times of day. 
 
 When it is found that the number of strides 
 required to traverse the distance is fairly uni- 
 form, take the average of the last half dozen 
 
52 SKETCHING METHODS 
 
 trials to determine your average for that dis- 
 tance. 
 
 In any method of constructing a scale, the 
 above steps must be taken. The further pro- 
 ceedings in the actual laying off and marking 
 off the scale may be accomplished in several 
 ways. Two ways considered the simplest and 
 easiest are given here. 
 
 The first method is to lay off on your paper 
 the scale distance in inches of the course and 
 divide it into as many parts and fractional 
 parts as you have hundreds and fractions of 
 hundreds of strides in your average. 
 
 Each full division will then show the length 
 on the working scale that will represent 100 
 of your strides at the desired scale. The 
 fractional division will represent an odd num- 
 ber of strides and may be erased, as there is no 
 need for it. 
 
 As an example, assume that you find the 
 average number of strides to cover a measured 
 1 mile course is 1048. Lay off a line 6 inches 
 .in length (the scale distance for 1 mile) and 
 divide it into 10.48 equal parts. 
 
SKETCHING METHODS 53 
 
 Each full division will show the distance on 
 your working scale which is required to repre- 
 sent 100 of yo.ur strides at a scale of 6 inches 
 to the mile. 
 
 To complete your scale, divide the left one 
 of the 100 stride divisions into 10 equal parts. 
 This part of the scale is called the extension 
 and is made in this way for convenience. Each 
 of the 10 parts in the extension represents 10 of 
 your strides. Mark the dividing line between 
 the extension and the main scale as zero and 
 then each dividing line along the main scale 
 between the other parts with the number of 
 hundreds of strides it measures from the zero 
 mark. 
 
 It should be remembered that when this 
 method is used, the line to be divided- in mak- 
 ing a scale corresponding to 6 inches to the 
 mile must be the same proportional part of 6 
 inches that the course on which the average 
 number of strides was secured, is of 1 mile. 
 That is, if the course is 1 mile, lay off 6 in- 
 ches; if it is 24 of a mile, lay off (%of 6 in- 
 ches) 4 l /2 inches; and if the course is l / 2 mile, 
 lay off ( J / 2 of 6 inches) 3 inches. 
 
54 SKETCHING METHODS 
 
 The second method is to ascertain the 
 length in inches or fractions of an inch which 
 will represent 100 of your strides. Having 
 this, lay off the number of divisions of that 
 length desired, mark them and paste them on 
 the ruler. For example : Assume that the 
 average number of strides to 1 mile is 1048. 
 It is desired to construct a working scale at 
 6 inches to 1 mile. Divide 6 by 10.48 and the 
 result, (.572 inches) will be the length on 
 your working scale which will represent 100 
 of your strides at 6 inches to 1 mile. 
 
 With a scale of equal parts (one reading 
 inches and tenths of inches will serve), lay off 
 as many divisions .572 inches long as you may 
 desire in your scale, and each of them will 
 represent 100 of your strides at 6 inches to 
 the mile. Mark off the extension and the 
 main scale as previously described, trim to suit, 
 and paste on ruler. 
 
 When a scale of strides for 6 inches to the 
 mile has been made, all that is necessary to 
 construct one at 3 inches to the mile, is to 
 take off on a piece of paper the divisions on 
 the 6-inch scale and mark them with just 
 
SKETCHING METHODS 55 
 
 twice the value they have at the 6-inch scale. 
 Each division of the extension will represent 
 20 strides at 3 inches to the mile. 
 
 Either of the foregoing methods may be 
 used in constructing a time scale for a horse. 
 It is first necessary that the horse should be 
 trotted and walked several times over a course 
 and his average time of travel secured. In 
 doing this, care should be exercised that the 
 horse's gait is not influenced by the presence 
 of another horse, the fact that the animal is 
 tired or fresh, that he is going towards or 
 away from the stable, etc. Allowances must 
 be made for such things, and practice enough 
 should be had, before constructing the scale, to 
 enable the sketcher to determine pretty well 
 whether or not the horse is taking a uniform 
 gait. 
 
 Working scales should be tested from time 
 to time by the sketcher in order to be sure that 
 his stride is not changing. This can be done 
 by occasionally checking traverses with a Geo- 
 logical Survey Map or by measuring with 
 chain and tape some of the distances traversed. 
 
56 SKETCHING METHODS 
 
 WHAT A SKETCH SHOULD SHOW 
 
 Broadly speaking, a military sketch should 
 show all natural and artificial features of the 
 surface of the earth in the area sketched. The 
 magnetic-meridian line, a title giving the char- 
 acter of the sketch, the locality sketched, the 
 date, the sketcher's name, the scale of the 
 sketch, and a graphic scale reading hundreds of 
 yards should also be shown. 
 
 Natural features (bodies of water, woods, 
 etc.) and all "works of man" are represented 
 by conventional signs, drawings to scale, or 
 by written words. 
 
 The configuration of the ground is repre- 
 sented by contours showing elevations and de- 
 pressions with the character of their slopes 
 and relative heights as truly as the scale of 
 the sketch, the time allowed and the sketcher's 
 ability will permit. 
 
 All detail, except that shown by contours, is 
 called flat or horizontal detail. That shown by 
 contours is called vertical detail. The military 
 sketch must have every feature located in its 
 relative horizontal and vertical position. 
 
SKETCHING METHODS 57 
 
 HORIZONTAL DETAIL 
 
 The horizontal position of any point is de- 
 termined when its direction and distance from 
 a previously determined point are shown. The 
 vertical position is determined when its eleva- 
 tion with reference to an assumed level, called 
 a datum plane, is shown. 
 
 The line from which all directions are meas- 
 ured is the plane of the magnetic compass 
 needle, called the magnetic meridian. The true 
 north and south line (true meridian) need not 
 be considered in sketching. It is most import- 
 ant when direction lines from one point to 
 another are located, that the sketching board 
 be "oriented" (explained under "Sketching 
 Board"). The sketcher should therefore 
 always verify the position of the needle or of 
 the arrow on his board before drawing a ray 
 (light line) toward the object whose direction 
 is being determined. 
 
 The position of a point, with reference to 
 direction and distance, is determined in one of 
 the following ways : (1) traversing; (2) in- 
 tersection; (3) resection; (4) estimation. 
 
58 SKETCHING METHODS 
 
 Traversing 
 
 By this is meant the measurement of the 
 distance between two points by counting* the 
 strides or time of travel required to pass from 
 one to the other. 
 
 The term traverse is applied to the route 
 followed by the sketcher, in making* the sketch. 
 
 To locate a point by traversing. Being at 
 point A (whose position is plotted on your 
 sketch) with the board oriented, stick a pin in 
 point A, on the sketch. Lay ruler alongside 
 the pin and pivot it around until point B 
 (the point to which you are to traverse) is 
 sighted. Verify the position of the arrow and 
 then draw a ray toward B. Move to B, count- 
 ing strides, and upon arrival lay your ruler 
 along the ray with the zero of scale of strides 
 at A and lay off on the ray the number of strides 
 that you took between the two points. The 
 point marked is B. 
 
 Intersection 
 
 The position of a point is determined in this 
 method by drawing rays toward it from each 
 of two other points whose positions are already 
 
SKETCHING METHODS 59 
 
 determined and plotted on the sketch. The in- 
 tersection of the two rays is the sketch posi- 
 tion of the point sighted. 
 
 To locate the position of a point by intersec- 
 tion. Assume that from point A, with your 
 board oriented, you took a careful sight and 
 drew a ray toward a church a few hundred 
 yards off to the side. After arriving at B and 
 plotting its position, you carefully orient the 
 board by a backsight on A. Pivot the ruler 
 around the pin in B until the church is sighted, 
 then draw a ray toward the church. The inter- 
 section of this ray with the one you drew 
 from A is the sketch position of the church. 
 
 Resection 
 
 This is determining the sketcher's position 
 by orienting the board and drawing rays 
 toward himself from two or more points 
 whose positions are already determined and 
 plotted. 
 
 To locate position b\ resection. After hav- 
 ing plotted the position of points A and B, 
 the sketcher comes into his area later at some 
 point from which those two points can be 
 
60 SKETCHING METHODS 
 
 seen. His present position is not yet deter- 
 mined. To determine it, set up the board and 
 orient as carefully as possible by the arrow, 
 then stick pins in. the sketch positions of points 
 A and B. Pivot the ruler around the pin at 
 A on the sketch until you sight A on the 
 ground and after verifying the position of the 
 arrow, draw a ray toward yourself. Next 
 pivot the ruler around the pin at B on the 
 sketch until you sight B on the ground, and 
 after glancing at arrow, draw a ray from that 
 point towards yourself. The intersection of 
 the two rays is the sketcher's position. 
 
 There are other methods of resection, but 
 their use is so exceptional that they need not 
 be considered. 
 
 Estimation 
 
 After some practice, points nearby are located 
 very accurately by simply estimating their dis- 
 tance and plotting their position on a ray 
 drawn toward them. Advantage is taken of 
 any feature in the locality that may assist in 
 determining the distance, such as telegraph or 
 telephone poles, fence posts, section lines, etc. 
 The ability to estimate distances should be 
 
SKETCHING METHODS 61 
 
 cultivated at every opportunity. A good 
 sketcher must be able to estimate with less 
 than 10 per cent error up to about 300 yards 
 and within 20 per cent up to a mile. This 
 ability can only be acquired by constant prac- 
 tice and by verifying the estimates by meas- 
 urements. All estimates should be made in 
 yards, and 100 yards should be definitely fixed 
 in mind as a reference unit. 
 
 Do not estimate on main traverse. 
 
 VERTICAL DETAIL 
 
 The U. S. Geological Survey uses sea level 
 as datum plane in determining elevations of 
 points. 
 
 In military sketches, the area is compara- 
 tively so small that the datum plane used is 
 immaterial. The reason for this is that what 
 is desired is the elevation of the different 
 points in the area with relation only to the 
 other points in it. It is immaterial whether 
 the elevation of the starting point is assumed 
 to be 500 feet or 1000 feet, but all other 
 points must then show their elevation with 
 reference to the assumed one. 
 
62 SKETCHING METHODS 
 
 It is well to ascertain the Geological Survey 
 elevation of some point and start from there, 
 because the sketch can be checked against a 
 Geological Survey Map more conveniently 
 when the elevations are the same, but it is not 
 at all necessary that this be done. 
 
 Under our normal system of scales the ver- 
 tical interval (V. I.) used on military maps and 
 sketches can be found by dividing the number 
 of inches representing one mile in the scale into 
 60. For example, at 6 inches to 1 mile the V. I. 
 is 10 feet. At 3 inches it is 20 feet and at 12 
 inches to 1 mile the V. I. is 5 feet. 
 
 The vertical position of a point is located 
 by determining its elevation above or below 
 some other point whose elevation has already 
 been determined. 
 
 The determining of difference of elevation 
 of two points by estimation is the method of 
 the experienced and rapid sketcher. After 
 some time and with considerable practice, the 
 sketcher acquires ability to estimate differences 
 with great accuracy. 
 
 There are many ways in which practice in. 
 estimating elevations may be had. The ability 
 
SKETCHING METHODS 63 
 
 to strike one's own level is of great value. 
 This can be practiced indoors by swinging the 
 extended arm around with the hand at level 
 of the eye, so that the line of sight over the 
 back of the hand passes through marks made 
 upon the wall at the exact height of the eye. 
 
 Having learned to strike your own level, 
 practice estimating distances or objects above 
 and below this plane by comparison with the 
 heights of ordinary objects in the vicinity, 
 such as telegraph poles, trees, etc. Fix in mind 
 a 10- foot unit and apply this to the height be- 
 ing determined. 
 
 In connection with estimating either hori- 
 zontal or vertical distances, it is well for the 
 beginner to remember that it is fatal to good 
 estimation to depend upon his judgment until 
 he has a definite and clear idea of what the 
 units of measure he is using really are, and 
 hence he should if possible check all estimates 
 until he has attained the ability to estimate 
 with a minimum of error. This will come 
 only with practice and constant checking. 
 
64 SKETCHING METHODS 
 
 Contours 
 
 The representation of vertical distances by 
 means of contours seems hard to the beginner. 
 This is largely due to the fact that the average 
 beginner usually attempts to contour before he 
 really knows what a contour is, what laws 
 govern their making, or what may be shown 
 by them at the scale being used. Before at- 
 tempting to do any contouring, in the field, 
 the beginner should gain a clear idea of these 
 things by careful study and much practice, so 
 that when he takes up contouring he will 
 know what he is trying to do. 
 
 Contours are lines drawn on a map or 
 sketch, which, following the various levels at 
 fixed vertical intervals, indicate the shape of 
 the ground and show its vertical irregularities. 
 
 The general laws governing the use of con- 
 tours may be fully learned only by actual field 
 work. Some are noted here: 
 
 1. Every contour line either closes on it- 
 self or both ends of it go off the sketch. 
 
 2. Every part of a contour line is at the 
 same level. 
 

 SKETCHING METHODS 65 
 
 3. A contour about to cross a stream line 
 runs up on one side of the stream and comes 
 down on the other, making a V where it 
 crosses. The apex of the V points upstream. 
 
 4. Contours representing spurs between 
 streamlines are generally U-shaped with the 
 bottom or rounded part of the U pointing 
 down hill. 
 
 5. Valley contours apparently go in pairs; 
 that is, the contour next to the streamline on 
 one side, is the same contour as the one next 
 to the streamline on the opposite side. If you 
 cross the 800- foot level just before you wade 
 into a stream, you must cross that same level 
 again when you wade out on the opposite side. 
 
 6. Ridge contours also apparently go in 
 pairs. The contour next to the top of a ridge 
 has its mate next to it just over the ridge. 
 
 7. In the case of the contours on opposite 
 sides of the stream, their meeting point will 
 generally be found close by; in those next to 
 the ridge top, it may be that they do not join 
 up on the sketch, but if the area were extend- 
 ed, their meeting point would be found sooner 
 or later. 
 
66 SKETCHING METHODS 
 
 In sketching, do not attempt to show a cliff 
 by contours. Break the contour lines on each 
 side and write "Cliff 60' " (or whatever its 
 height may be). Do the same with a bluff 
 which is so high and steep as to make diffi- 
 cult clear representation by means of contours. 
 If you have a depression to represent, be sure 
 that the contours showing it are clearly num- 
 bered so that it may at once be understood. 
 
 Detail Shown by Contours 
 
 The amount of detail that may be shown 
 by contours depends directly upon the scale of 
 the sketch. Failure to realize this is one of 
 the reasons why the representation of ground 
 forms by contours is often difficult for the 
 beginner. For example, on a scale of 3 inches 
 to the mile, a spur 100 feet long jutting out 
 from a hillside would cause a contour line to 
 change about 1-20 inch, the scale width of the 
 spur. If trouble were taken to change an 
 otherwise regular contour to indicate this, no 
 one would notice it nor care anything about it 
 if it were noticed. It is true that this spur 
 might furnish cover to a number of the enemy, 
 
SKETCHING METHODS 67 
 
 but when the commander wants a sketch in 
 which such cover becomes important, he will 
 have it made on a larger scale. 
 
 The minimum size of ground features that 
 can be shown to advantage to the scale used, 
 should be determined and kept clearly in mind 
 by the sketcher. Then so far as anything 
 smaller is concerned, he should regard the 
 ground as smooth and regular. This will 
 greatly simplify his work. 
 
 It must be realized that any details that can- 
 not be shown clearly and naturally to the scale 
 ordered, are not wanted. This, of course, 
 refers only to those features that are to be 
 shown to scale. Houses, bridges, roads, 
 streamlines, etc., being represented by conven- 
 tional signs, are riot drawn to scale. 
 
 A good method to follow to gain an idea 
 of what can be shown at the various scales by 
 contours is to take a map or sketch of an area 
 and carefully study the ground represented 
 and note the smaller details that are not shown 
 on the map. Compare map and ground, again 
 noting carefully the ground forms as they are 
 
68 SKETCHING METHODS 
 
 on the ground and then how they are repre- 
 sented on the map. 
 
 A box filled with sand, called a sand table, 
 is a great aid in studying ground forms and 
 may be used if time permits and outdoor work 
 cannot be done. Many exercises can be held 
 in which much can be accomplished in learn- 
 ing how to contour. Make a mound, assume a 
 scale, and represent it by contours. After 
 drawing in the flat detail of a sand-table 
 terrain, contour the area, first determining the 
 elevation of the critical points, then spacing 
 the contour points by eye according to the 
 slopes, and then connecting up the levels. 
 
 Take a section of a contoured map and repro- 
 duce it on the sand table according to scale. 
 Later, without looking at the contoured map, 
 make a sketch of the area and compare it 
 with the contoured map. 
 
 Any ground forms can be produced and 
 their contour lines studied out and drawn. 
 The amount of work that can be done on the 
 sand table depends upon the time the student 
 will give to it and his ingenuity. 
 
SKETCHING METHODS 69 
 
 The value of the sand table is, of course, 
 limited to giving a thorough understanding of 
 ground forms and of their representation by 
 contour .lines. This understanding is essential 
 to the sketcher. Practical familiarity with 
 ground forms and ability to represent them 
 correctly can only be gained on the ground, 
 for the only way in which the ground perspec- 
 tive can be appreciated, is by study of the 
 ground itself. To the beginner, ground dis- 
 tances appear greater and features nearby 
 larger than they actually are, and this can only 
 be corrected by actual work on the ground. 
 
 Logical Contouring 
 
 The Engineer Department at the Army 
 Service Schools at Fort Leavenworth has had 
 printed a number of plates for the purpose of 
 practice in drawing contours. These show 
 the flat details of the area and the elevations 
 of critical points. The entire series should be 
 filled in by every beginner and corrected by an 
 instructor before attempting any field work 
 other than filling in flat details. The series 
 consists of several sheets, each with four areas. 
 
70 SKETCHING METHODS 
 
 These can be secured at small cost from the 
 Book Department, Army Service Schools. 
 Too much of this practice cannot be had. The 
 method of filling in the contours is illustrated 
 in Figs. 8, 9, 10 and 11. 
 
 Practice in logical contouring, as it is called, 
 is most necessary to a clear understanding 
 of contouring in sketching. The more of it a 
 student does the better. Anyone can make up 
 a framework, similar to those shown in Figs. 
 8, 12 and 13, and practice contouring by logi- 
 cal methods. 
 
 The procedure, as shown, is to first note the 
 elevations of critical points along stream lines 
 and ridges, then divide up and mark crossing 
 points of contour lines along the main stream 
 line, then along the tributary streams, mark- 
 ing those on stream lines with a V pointing 
 upstream, then from points along the stream 
 lines to ridge-line points nearby, mark (with 
 dots or short lines) the crossing points of the 
 number of contour lines that go between, ac- 
 cording to the elevations of the top and bot- 
 tom points. Finally, having enough of these 
 
SKETCHING METHODS 71 
 
 to shape the ground, join them up by long 
 curving lines. 
 
 On all sketches, the contour lines should be 
 numbered so that the elevation of any one of 
 them can be readily found. They should be 
 numbered where they leave the area and occa- 
 sionally along a stream line or on some of the 
 longer slopes (fig. 11). The completed sketch 
 should have each 50 or 100 foot contour line 
 drawn heavier than the others. 
 
 Contour Framework 
 
 Critical points are those at which an abrupt 
 change in direction or slope takes place, such 
 as bends in roads or streams, stream junc- 
 tions, tops of ridges, hills, etc. Any feature 
 which may assist the sketcher in securing his 
 framework, may be called a critical point. 
 
 Manifestly, it is impracticable to determine 
 the exact location of the crossing points of 
 each contour line between all the critical 
 points. It is equally impracticable to deter- 
 mine the location of every slight change of 
 slope on a hillside. Such detail is not im- 
 portant and is not wanted. Hence, the 
 
72 
 
 SKETCHING METHODS 
 
 Fig. 8 
 
 Arrow heads on Figr. 8 snow direction of water flow 
 Place 10'Contours on the above sketch . 
 
 Arrow points on Fig. 9 [except those also appearing on Fig. 8] are points 
 
SKETCHING METHODS . 73 
 
 Fig. JO 
 
 Fig.ll 
 
74 SKETCHING METHODS 
 
 sketcher ascertains the elevation of critical 
 points, thus locating the position of the form- 
 controlling contours and interpolates the con- 
 tour lines between them, spacing by eye to 
 indicate the change of slope as these changes 
 appear to him. 
 
 The undulations and vertical distances in 
 the form of the ground are largely caused by 
 the erosive action of rainfall, hence the drain- 
 age system and ridge lines form the frame- 
 work on which contours are hung. 
 
 If the sketcher determines: (1) the eleva- 
 tion of the main stream line at the point where 
 it enters his area; (2) the elevation of its 
 junction with its tributaries, in the area; 
 (3) the elevation of the main stream where it 
 leaves the area : he will have a good base from 
 which to build up his contours. If while de- 
 termining the above, he also determines the 
 elevations of the tops of the ridge lines be- 
 tween the stream branches and of important 
 points along and on these ridges, he will have 
 the highest as well as the lowest levels in the 
 area and need only fill in the contours between 
 the points whose elevations are known. 
 
SKETCHING METHODS 
 
 75 
 
 The foregoing is exactly what the sketcher 
 must do in contouring. As he goes over his 
 area, drawing to scale the flat or horizontal 
 details, he locates all critical points and esti- 
 mates and notes their elevation. Then, having 
 enough of the drainage system and ridge lines 
 "pinned down" to enable him to show the big 
 features, he dots in the level lines at their 
 
76 SKETCHING METHODS 
 
 proper vertical intervals between critical points 
 according to the slope of the ground. Finally, 
 he connects up the clotted points by contour 
 lines, each running through the dots of its 
 own elevation. 
 
 In reality, contour lines in sketching are 
 nothing more than conventional signs. A 
 sketcher will soon find that every slope is one 
 of three kinds, uniform, concave, or convex. 
 When spacing in contours, this should be kept 
 in mind. Any slope of ground may be 
 divided into sections, each of which may be 
 represented by one of the three kinds men- 
 tioned. Practice alone will enable one to pick 
 out the dividing lines, but they should be 
 looked for from the beginning. 
 
 Where the slope is uniform, space your con- 
 tours equal distances apart; where the slope is 
 concave in form, space your contour lines 
 closer together near the higher elevation and 
 wider apart toward the lower; where the slope 
 is convex, space them wider at the higher and 
 closer at the lower elevation. 
 
 The beginner must learn to consider general 
 knowledge of country, of rates of fall of 
 
SKETCHING METHODS 
 
 77 
 
 streams, of railroad grades, and of ground 
 forms in order to keep his work logical and 
 consistent. For instance, large rivers have a 
 fall of only a few inches to the mile, unless 
 there are many rapids; therefore, within the 
 limits of an ordinary reconnaissance sketch, a 
 large river is at the same level, for purposes 
 
 IOQOJ | ? A,sa* J. 7 bgj I [i030 
 
 .000] [ 
 
 Interpolate lO'Contours. 
 
78 SKETCHING METHODS 
 
 of determining elevations. A stream line 
 carrying water all the year round has a less 
 fall per mile than one in the same area which 
 is dry part of the time. Tributary streams 
 have a greater fall than main stream lines. 
 The nearer the stream to the source, the 
 steeper it falls. 
 
 NOTES FOR FIELD WORK 
 
 Avoid complicated and cumbersome methods. 
 
 Always use the simplest and most common- 
 sense way. 
 
 Do everything possible, consistent with re- 
 quirements of making the sketch, to save time. 
 When you halt to make a note, make it, and 
 go on. When you halt to fill in something 
 and it is not necessary to orient, do not orient 
 but do the filling in quickly, and move on. 
 
 Never orient the board unless there is neces- 
 sity for it. 
 
 Every time you orient the board by arrow 
 or compass, verify it by a backsight, if prac- 
 ticable. Every time you orient by a backsight, 
 verify it by the arrow or compass. 
 
SKETCHING METHODS 79 
 
 Always verify the orientation just before 
 you draw a ray either along a traverse or in 
 intersection or resection. 
 
 Try to acquire the habit of doing the neces- 
 sary things at each halt in the same sequence. 
 For example, traversing along a road, you 
 arrive at the top of a rise, to which you had 
 drawn a ray. Halt there, look around, and 
 select the best position for sighting forward 
 on the traverse. Lay the board down on the 
 ground or place it on your knees. Take out 
 ruler and pencil, and placing ruler alongside 
 the ray with edge of working scale next to it, 
 measure off the number of strides from last 
 station and mark with pencil dot. Stick a pin 
 in this dot which is your present station. Lay 
 ruler along ray to last station and orient board 
 by backsight. Having the board oriented, 
 pivot the ruler around the pin and draw a ray 
 to the next station. Now sight and draw rays 
 to such points as you may have drawn rays to 
 from previous station, to complete their loca- 
 tion by intersection and then draw rays to 
 such new points as in your judgment may be 
 of use, noting in each case the object sighted. 
 
80 SKETCHING METHODS 
 
 Verify orientation each time before drawing 
 ray. Now draw in the other road line (the 
 ray taken to this station is one) and fill in 
 the flat details, houses, bridges, stream lines, 
 fence signs, etc., from the last station to your 
 present one. Determine the elevation of youi 
 present station by estimating the difference be- 
 tween it and the previous one. In the same 
 manner determine the elevation of any critical 
 points that you may have noted in your 
 traverse from last station as well as of points 
 located by intersection. If you have enough 
 data to enable you to contour between stations, 
 do it now; if not, be sure that the elevations of 
 critical points are noted. Put the ruler, pencil, 
 eraser, pin, etc., in their proper places, pick up 
 the board, and start traverse to next station. 
 
 The operations noted in the foregoing have 
 to be carried out at each station. Failure to 
 carry them out in sequence while learning to 
 sketch will handicap the beginner very much. 
 It is therefore considered essential that the 
 beginner should learn to do them in the 
 sequence described. After a while he will de- 
 velop the simplest and best way for himself. 
 
SKETCHING METHODS 81 
 
 Have your sketch completed up to your 
 station before moving on. In the earlier 
 stages, this applies only to flat details, later to 
 both horizontal and vertical detail in road 
 sketching and to horizontal detail and the loca- 
 tion and determination of the elevation of crit- 
 ical points in making a position sketch. The 
 contouring in this case is not undertaken until 
 the entire framework of ridge and stream lines 
 is "pinned down." 
 
 Be particular that the information conveyed 
 is not misleading. It is better to leave a part 
 blank than to deceive or mislead. 
 
 Try to put equal care and time on all parts 
 of the sketch. Avoid excessive care at the 
 beginning followed by excessive haste near the 
 end. 
 
 Acquire method and system in your sketch- 
 ing and the rest will be easy. 
 
 POSITION SKETCH 
 
 It is assumed that before undertaking to 
 make a position sketch, the sketcher has fol- 
 lowed out the course of study outlined herein. 
 
 Select an area of ground about one-half a 
 
82 SKETCHING METHODS 
 
 mile square. One having roads on all sides 
 is better, but this is not material. 
 
 Determine where to locate your starting- 
 point on the paper by estimating the direc- 
 tion from you in which the area to be 
 sketched lies. If you are at the southwest cor- 
 ner of the area, locate your starting point (by 
 sticking in a pin) about 5 inches from the 
 west edge and 5 inches from the south edge 
 of the paper. Since the area to be sketched 
 will occupy about 3 inches square when drawn 
 to scale, you will thus have it at about the cen- 
 ter of the sheet. 
 
 Draw the magnetic meridian line parallel to 
 the edge of the paper, then orient board. Take 
 forward sight to next station and draw ray 
 towards it. Assume elevation of starting point 
 and note it. Now traverse all the way around 
 the area, locating as you go the position and 
 elevation of all critical points along the trav- 
 erse. Fill in all horizontal detail along and 
 near the traverse, inside the area, within easy 
 estimating distance (a couple of hundred 
 yards) by estimation and farther off by inter- 
 section methods. 
 
SKETCHING METHODS 83 
 
 In traversing around the area, in addition to 
 cuts, fills, orchards, etc., locate the following: 
 
 1. Every stream or drainage line crossing 
 the traverse or running close to it. Note 
 the direction of its flow and its fall. If 
 this is not at once apparent, take time to 
 find out. This is important. 
 
 2. Every house or other feature easily iden- 
 tified near the traverse, which may later 
 be useful in finding yourself. Sometimes 
 some feature outside of the area may 
 be extremely valuable. For example, a 
 tall chimney some hundreds of yards 
 from the area may be visible from all 
 points in it; to locate this by intersection 
 early in the work may save much time 
 later. 
 
 3. The high points between drainage lines 
 along the traverse (determine and note 
 their elevations). Proceeding simulta- 
 neously with the traversing, dot in (ac- 
 cording to the slope of the ground) and 
 mark the crossing points of the contours 
 between critical points along the traverse 
 
84 SKETCHING METHODS 
 
 whose elevations have been determined. 
 Do not draw any contours yet ; wait until 
 later when you have the stream line and 
 ridge framework completed and can see 
 the area as a whole. The big features will 
 then be distinct, and the little ones will 
 take care of themselves. 
 
 ADJUSTMENT TO CLOSE. 
 
 When you reach a point from which the 
 starting point can be seen, you will probably 
 find that the ray to that point does not pass 
 directly through it. This is to be expected. 
 If the error. is less than 10 per cent of the 
 entire length of the traverse, it is satisfactory. 
 If it is greater, there has probably been some 
 error in your orientation. If you are not able 
 to determine just where the mistake occurred, 
 distribute the error by adjustment. To do this, 
 move the last point to or from the point of 
 starting, the next traverse line a little less in 
 the same direction, and the next one a little 
 less than the previous one. Remember the 
 scale you are using and the scale width of a 
 road as it is drawn on the sketch. Do not 
 
SKETCHING METHODS 85 
 
 waste time in making this adjustment, but in 
 making" it, be sure that you do not make an 
 angle between roads which is noticeably dif- 
 ferent from the actual ground angle made by 
 the roads. Otherwise some one may be mis- 
 led. Your sketch will have errors in it, but it 
 must not contain misleading or deceptive in- 
 formation. 
 
 COMPLETING SKETCH. 
 
 Having traversed completely around your 
 area and having noted the location of all 
 drainage lines crossing its borders, you will 
 have a pretty fair idea as to which is the main 
 stream line and where it lies. You must now 
 find out how the smaller stream lines connect 
 up with it in the area in order to complete 
 your framework. It is now time to traverse 
 into the interior. Select a road or trail if one 
 is nearby; if not, select some point in the in- 
 terior and draw a ray to it, being careful with 
 the orientation when you draw it. Traverse 
 along the road or ray and keep going until it 
 seems advisable to stop. Then plot your posi- 
 tion, fill in flat detail up to your location, deter- 
 
86 SKETCHING METHODS 
 
 mine your elevation, and then, after orienting 
 the board, draw rays to such stream junctions 
 and high points as seem to be valuable. In this 
 manner, traverse across the entire area, locating 
 stream lines, stream junctions, ridges and hill- 
 tops, fill in flat detail, determine elevations as 
 you go and note those of critical points along 
 and ne^r your traverse. It may be necessary 
 to traverse across the area in the other direc- 
 tion before all critical points are determined, 
 but on such a small area, it will probably not 
 be. After having 'located the drainage frame- 
 work and ridge lines and determined their 
 elevations, you are ready to contour. This 
 should be done by noting the slopes as uni- 
 form, concave or convex and spacing the con- 
 tour lines accordingly. After a little practice, 
 it should be possible to contour any area that 
 the sketcher has been over, from one or two 
 places from which he is able to see the slopes. 
 Until the sketcher becomes pretty familiar 
 with ground forms and their representation by 
 contours, he should take time to dot in the 
 crossing points of the contour lines between 
 all adjacent critical points. This will take a 
 
SKETCHING METHODS 87 
 
 little longer, but will save much time later 
 because of the practice it gives the hand and 
 eye. 
 
 Put on the title as described on Page 43, 
 and the sketch is finished. 
 
 OUTPOST SKETCH 
 
 In the execution of an outpost sketch, which 
 is made on a scale of 6 inches to the mile, 
 V. I. 10 feet, the methods followed are the 
 same as those of a position sketch, except that 
 the sketcher is confined to one side of the area. 
 
 Points along the outpost line are located by 
 traversing, while those to the front are de- 
 termined by intersection or, in some cases, by 
 estimation, as for instance, where a feature 
 can be seen from one place on the line only. 
 
 Having made two or three position sketches, 
 the beginner should be able to start at one end 
 of the line and carry his operations along to 
 the other end and then from some advantageous 
 position contour the area. 
 
 A little study of the area before starting 
 the sketch will be of value in determining the 
 best method to follow. 
 
88 SKETCHING METHODS 
 
 Traverse the outpost line, sketching it as 
 you go, and drawing rays from different sta- 
 tions to points in the foreground, thus locating 
 them by intersection. 
 
 The angle between the intersection lines 
 should be as near 90 degrees as possible. There- 
 fore, the points on a straight line from which 
 the intersecting lines are drawn, should be far 
 enough apart, if the ground will permit, to 
 secure this. It is thus evident that the farther 
 out the points are, the farther apart should be 
 the points from which the intersecting lines 
 are drawn. Conversely, the nearer the ob- 
 ject, the shorter need be the distance between 
 the points on the traverse line, from which the 
 rays are drawn. 
 
 The distance to be sketched to the front de- 
 pends upon the time available and the char- 
 acter of the country. In all practice work, the 
 sketcher should include the area as far to the 
 front as he can see. 
 
 It is frequently the case in outpost sketch- 
 ing that it is possible to locate and draw in one 
 end and the direction line of a straight road, 
 fence line, railroad track, or telegraph line. 
 
SKETCHING METHODS 89 
 
 If this can be done, all points along it are 
 accurately located by drawing a ray to them 
 from determined points along the traverse, 
 thereby completing the intersection. 
 
 In contouring the outpost sketch, the same 
 methods are followed as in the position sketch. 
 Ttie stream line and ridge frame work have 
 been secured by the sketcher in his traverse, 
 and it only remains to interpolate the contours 
 according to the slopes of the ground as they 
 appear to the sketcher. 
 
 Any part of the area that cannot be seen, 
 as the far side of a ridge parallel to the trav- 
 erse, is drawn in by broken contour lines, 
 which indicate that, in the opinion of the 
 sketcher, the ground is shaped as shown by 
 them although he has not visited it. 
 
 Field glasses may be of use in outpost 
 sketching in picking out objects on which to 
 intersect or for discovering folds in the ground 
 that are not visible to the naked eye. 
 
 PLACE SKETCH 
 
 A place sketch is one in which the sketcher 
 is limited to a single point of observation over- 
 
90 SKETCHING METHODS 
 
 looking the area to be sketched. The details 
 to be shown are the same as on a position or 
 outpost sketch. 
 
 If made to extend a road or position sketch 
 farther toward the enemy than can be reached 
 by the sketcher, the place sketch will be at the 
 scale of the sketch thus extended, otherwise 
 at 6 inches to the mile and 10- foot V. I. 
 
 The methods of work described for making 
 a position and outpost sketch are followed, ex- 
 cept that the location of points is determined 
 by estimation, assisted by intersection methods 
 where possible. 
 
 It is advisable to select some few prominent 
 features in the area, determine their position 
 and elevation as carefully as possible, and then 
 use them as reference points in locating other 
 points. A road, a hedge fence, a wire fence, 
 a railroad or any such feature should be locat- 
 ed and drawn in as soon as possible and used 
 for basing other estimates and for locating 
 points along it by intersection. 
 
 Parts of the area that cannot be seen but 
 which the sketcher is able to estimate, should 
 
SKETCHING METHODS 91 
 
 be represented by broken lines, as in outpost 
 work. 
 
 Place sketching is extremely valuable to the 
 beginner who has progressed through position 
 and outpost sketching, on account of the prac- 
 tice that it gives in estimating distances. 
 
 ROAD SKETCH 
 
 Before taking up road sketching, the be- 
 ginner should be able to make a position sketch 
 and should have made a few outpost and place 
 sketches, for the benefit of the practice in in- 
 tersection and estimation which he gains by 
 them. He should also learn something of what 
 can be shown to advantage on a 3-inch scale. 
 
 It is advisable to make one or two short 
 road sketches dismounted before taking up the 
 road sketching proper, which is done mounted. 
 
 The methods followed in road work are a 
 combination of those used in the other classes 
 of sketches which have been described. The 
 scale is usually 3 inches to 1 mile with V.- I. 
 20 feet. The sketcher lays the board on the 
 ground or places it on his knees as he sits down. 
 
92 SKETCHING METHODS 
 
 The road sketch should include all the 
 country for 400 yards to each side of the road, 
 all artillery positions within several miles and 
 all commanding positions within rifle range of 
 about 1 mile. It should show any prominent 
 landmarks and where roads, railroads, etc., 
 come from and go to, the names of rivers and 
 larger streams, of the families living at cross 
 roads or in isolated houses, of towns or vil- 
 lages, as well as all information that is given 
 in position, outpost, or place sketches. 
 
 Arriving at his second station, the sketcher 
 should draw in not only all horizontal detail 
 from the first station but should contour the 
 area he has passed over before starting on his 
 next traverse. It is for this reason that it is 
 considered better for the beginner not to at- 
 tempt to make a road sketch until he is some- 
 what practiced in sketching methods. 
 
 Do not waste time in orienting, but after 
 laying board down or standing up with it 
 leveled in front of and pressed against the body, 
 orient by backsight, and check by noting that 
 arrow on board is to north. 
 
SKETCHING METHODS 93 
 
 With the board held pressed against the 
 body, to draw a ray to a distant object, first 
 orient the board, then pivot the ruler around 
 the pin to its approximate position, and glanc- 
 ing down at the ruler and at the object alter- 
 nately, determine when the ruler is pointing at 
 the object. Glance at the orientation, care- 
 fully secure the ruler with finger or thumb, 
 and then draw the ray. This will be found 
 quite difficult to do at first, but a little prac- 
 tice will make it easy. Points determined by 
 intersection of rays taken in this manner are 
 very accurately located after some practice. 
 
 The road sketch is carried along in the man- 
 ner indicated from station to station, being 
 completed at each point before moving on to 
 the next. 
 
 Many points within 400 yards of the road 
 will not be visible to the sketcher from his 
 position opposite them in the road, but they 
 may be from some point further on. In any 
 case, make it a rule not to leave the road. Fill 
 in such places as you think they are, as de- 
 scribed in outpost work, or leave them blank, 
 
94 SKETCHING METHODS 
 
 as their character will be seen by the reader 
 of the sketch. 
 
 In case the sketch should threaten to run off 
 the paper, the procedure is to fill in the detail 
 a little beyond your station (which is now 
 close to the edge of the paper) and then, 
 choosing a new point of beginning on the 
 paper, locate your station there, draw a mag- 
 netic-meridian line nearby, and duplicate the 
 filling in previously done, around and be- 
 yond it. 
 
 Go right ahead with this part just as though 
 the other part was a different sketch, but when 
 the sketch is finished, cut the paper between 
 the two parts, and laying the points which 
 you filled in twice (once near the edge of the 
 paper and again when you started the new 
 part), one over the other, turn the papers 'un- 
 til the M. M. lines of the two parts are par- 
 allel, and then paste them together in that 
 position. The sketch may run off the paper 
 several times, but so long as the finished sketch 
 shows the meridian lines of all different parts 
 parallel to each other, this is immaterial. 
 
SKETCHING METHODS ^ 
 
 In mounted work, the sketcher must, while 
 controlling the horse and riding along the 
 road, jot down the features as they are passed. 
 This is done on the pad as described on 
 Page 34. 
 
 Practice in noting down features w r hile 
 riding at a trot should be had before going 
 out to make a sketch. It is quite difficult for 
 some to learn, but anyone can do it with 
 practice. 
 
 System in methods of work is most impor- 
 tant, as time is a big factor in mounted work. 
 All sketching is done as in road sketching dis- 
 mounted. The board is swung under the left 
 arm by the cord passing over the shoulder, and 
 m the watch (if using the stop watch) and pad 
 are held in the left hand, finger close to the 
 stop of the watch. Using the stop watch and 
 pad is largely for convenience. Satisfactory 
 mounted work may be done by using an ordi- 
 nary wrist watch on inner side of left wrist, 
 from which the time of passing a feature, etc., 
 may be noted on a pad held in left hand. 
 
 The reins are held in the right hand, over 
 left wrist, or with a knot tied in them across 
 
96 SKETCHING METHODS 
 
 the pommel of the saddle where they can be 
 quickly grasped. 
 
 If you have an assistant, which is desirable, 
 have him carry the board and hold your horse 
 when you halt. The assistant should be with 
 you while rating the horse and ride either 
 abreast of or behind you as he is to do during 
 the sketching. 
 
 Immediately after mounting, take the pad 
 in left hand. As the horse starts, press the 
 stop, being careful to see that stop watch is at 
 zero. 
 
 Keep your eyes on the country and on your 
 watch alternately so that when you see a fea- 
 ture, you will not have to hunt for the proper 
 place on the pad to locate it. It may be nec- 
 essary at first to stand in your stirrups and 
 lean forward with arms close in while making 
 the marks in order to get readable ones. Note 
 the direction erf flow of the stream lines as 
 you pass them. 
 
 At first, traverse about a minute at a time 
 and then dismount and complete the sketch in 
 the same manner as in road sketching dis- 
 mounted. The time spent in traversing is 
 
SKErCIIf\(; METHODS 97 
 
 small in comparison with that spent in plot- 
 ting the notes taken. 
 
 Arriving at a halting place, stop the horse, 
 press the watch stop to secure correct time or 
 note same from watch, throw sketch-board 
 cord over the head and lay the board on the 
 ground, or sit down and place it on your knees. 
 It is better to lie down on the ground on the 
 stomach and with pad at hand and the board 
 on the ground, measure off the minutes of 
 travel and fill in flat detail and critical points 
 according to the notes. Then orient the board 
 and draw a ray to the new station or in the 
 new direction along the traverse. Then, tak- 
 ing the board up as previously described, con- 
 tour the sketch up to your position. 
 
 In field service, the information desired in 
 a road sketch is largely that which will en- 
 able another to follow the reconnoitered road. 
 For this reason, contouring is of less impor- 
 tance than direction, distance, land-marks, 
 and condition and practicability of roads. In 
 learning how to sketch, however, it is consid- 
 ered-necessary that the sketcher practice con- 
 touring in road sketching, not so much because 
 
98 SKETCH IXC METHODS 
 
 he will do this in service as because the prac- 
 tice in rapid contouring is invaluable in the 
 study of ground forms and their representa- 
 tion. 
 
 RECONNAISSANCE SKETCHES. 
 
 The tactical situation and the intentions of 
 the commander will indicate in each case the 
 information that is especially desired. The 
 information secured is conveyed by means of 
 a sketch amplified by a report in marginal notes 
 numbered serially. All information that it is pos- 
 sible to show clearly is contained in the sketch. 
 The report consists of descriptions of features 
 and objects, measurements, material, construc- 
 tion, etc., which cannot be conveyed in a sketch. 
 The serial reference numbers should run in 
 order on the margin. The numbers are placed 
 on the sketch near the object to which they 
 pertain, so that it will be clear to what they 
 refer. In making the notes, clearness and 
 brevity are desirable. Such terms as before, 
 behind, this side of, etc., should be avoided and 
 compass directions used. The terms left and 
 right may be used in referring to the banks of 
 a stream in which case the sketcher is assumed 
 to be facing down stream. 
 


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