Before commencing the work summarize the important points involved.

  1. If possible select a base line.
  2. Locate as many points by intersection as possible.
  3. Make traverse by road, check locations by resection.
  4. At good observation points observe and complete the sketch as far as possible.

At each station keep the following points in view:

  1. Back sight on previous station.
  2. Select new sighting point ahead.
  3. Determine elevation by slope board.
  4. Put in contours where possible noting the drainage and critical points of the general slope and the terrain.
  5. Put in details along traverse just made of all topographical features of military importance.
  6. Determine your present elevation.
  7. Make as many shots for intersection as you can and mark them.
  8. Look for possible resection shots.

Lessons 9 And 10. (Field Work—nine Hours.)

Problem.—Make a road sketch of about 12 miles with scale of 3 inches to the mile, V.I. 20 feet. This should include details of military importance to a distance of 300 yards on either side of the road.

Keep in mind these points:

  1. Start carefully and give attention to every part of the map.
  2. Keep the board properly oriented.
  3. Watch the water drainage systems.
  4. Put down all necessary details at each setup.
  5. Note high hills and towns not on immediate route, condition of roads, fences, cultivation, hedges, cuts and fills, bridges (kind and length), railroads, telegraph and telephone lines, schools, churches, etc., notice particularly woods and points of concealment for hostile troops.

Do the work at each station for elevation, contours and the noting of necessary details so that the sketch will be complete as you go along. Make certain that the title of the sketch, scale, orientation, etc., are all clearly indicated, for a road map may have to be completed by another or may be called for suddenly when it will be useless without these details.

Remember there are but two things absolutely essential to a good road sketch; a good traverse and the location of the drainage system in its relation to this traverse. With this control approximate contours can be drawn by anyone having a knowledge of the principles of topography. Never plot unimportant details. Prominent buildings and farm houses are of value for locating oneself. Woods and orchards are shown for tactical reasons but no one can expect to show every fence, ditch or bit of cover that might hide a patrol.