COMPASS AND PACING 95 



shown in illustration is the pattern of the U. S. Forest 

 Service. The base is flat so that the instrument may be 

 used to orient a plane table it is square also and gradu- 

 ated on its edges with a protractor and two scales for draft- 

 ing purposes; declination can be set off by means of a 

 vernier; inside the box a pendulum is fitted and the staff 

 mountings permit of turning the instrument and holding 

 it edgewise while employed as a level or clinometer. 



STAFF COMPASS 



A main use for the staff compass in topographical and 

 timber work is for making foot traverses, a purpose for 

 which it is thoroughly adapted. The common pocket 

 compass with needle l to 2 inches long, indeed, may be 

 used for the same purpose, and when it enables a man to 

 travel a mile with only 1 or 2 of angular swing, as it 

 will do if carefully used, it deserves to be called a surveying 

 instrument. 



Pacing. The pace has been long used as a check on 

 short distances, but the real capacity of pacing as a method 

 of measurement has only recently been developed. It 

 is of special value to woodsmen who must travel their 

 country over in any case, and who by a little extra pains 

 taken in this direction can bring out much valuable infor- 



