A Plane Table Sketching Case. 217 



1. Jacob staff. 



2. Forest Service Standard Compass with staff mountings. 



3. Plane table-sketching case. 



4. Abney hand level with aneroid, if desired. 



5. Tally register. 



6. Pencils and map sheets and eraser. 



With this equipment the compass-man can do triangulation in 

 addition to getting the data gathered by the old methods. If the 

 conditions do not allow such work, the Jacob staff can be left in 

 camp. 



The following is a description of the plane table-sketching case 

 as designed : 



The plane table-sketching case is to be constructed of aluminum 

 and hardwood strips and veneers. The total thickness of the 

 plane table does not exceed one-half inch, and the total weight as 

 designed will not exceed two and one-half pounds. The entire 

 plane table with staff mountings attached can be carried slung 

 over the shoulder suspended by raw hide laces or carrying straps. 

 When sights are taken at each station the compass-man picks the 

 plane table from the Jacob staff and throws the straps over his 

 shoulder- The Jacob staff is carried in the left hand. The 

 Forest Service standard compass is carried in its case or in the 

 pocket. 



The plane table-sketching case is designed to afford protection 

 to completed and unused map sheets. The space below the upper 

 aluminum plate is for this purpose. An extra paraffin paper 

 envelope of a size to enclose about six map sheets is slipped into 

 this drawer or space. When a sheet becomes wet the wet sheet 

 is placed outside of the wax paper envelope but inside the drawer. 

 Thus dry sheets are always separated from wet sheets, and both 

 wet and dry sheets are protected from injury. 



Only one map sheet is exposed and mounted at one time. The 

 cover clamp when raised opens the drawer containing the map 

 sheets at the same time releasing the finished map sheet. The 

 new sheet is withdrawn from the envelope and the finished map 

 enclosed. By laying the clean sheet upon the board and snapping 

 down the cover clamp the map sheet is held down fast without 

 marring the surface with thumb tack holes. At the same time 

 the drawer is automatically closed against dirt and moisture. 



Clean, dry map sheets are kept separate from the wet map 



