====== 3.1.2.2- UNITS ======



By default, lenght units are meters and angle units are (360) degrees. If
you use (400) grades instruments and say, yards as lenght units, your .th
file should have lines for it. Here is an example:


 survey FOO -title "FOO Cave"
   centerline
   units lenght yard
   units compass clino grad
   data normal from to length compass clino
  
   (survey data here)
  
   endcenterline
 endsurvey