32 A MANUAL FOR NORTHERN WOODSMEN 
cuit of a farm’s boundaries by compass and chain is a 
traverse. So is the survey of a road by usual methods. 
When a survey has been made in this fashion the notes 
are for some purposes best worked up after a method 
called “ computing by traverse,” the principles and appli¬ 
cations of which are developed in the following paragraphs. 
If a course is run out N 30° E 20 chains, a certain dis¬ 
tance is made in a northerly direction, also a certain dis¬ 
tance in a direction east. The distance made in the former 
direction is called latitude ; in the latter, departure. In this 
case it is north latitude and easterly departure. These 
elements may be made evident on a plot by drawing a 
meridian and base line through the starting point and 
lines perpendicular to these from the point reached. These 
distances are also to be obtained from traverse tables. 
The same is true of a course run in any direction and 
for any distance. Any course not run exactly east and west 
makes northing or southing. The former is reckoned as 
positive latitude, with the sign (+). The latter is negative 
or (—) latitude. Similarly, distance made in an easterly 
direction is (+) departure; that made towards the west 
(—) departure. If several courses are run in succession, 
the sum, algebraically reckoned, of their latitudes and 
their departures gives the position of the point finally 
attained. 
This method of reckoning, using traverse tables for the 
purpose, has a wide use in connection with land surveying. 
The traverse table given on pages 214-219 furnishes the 
elements for 15' courses, those usually employed in com¬ 
pass work. The following is a simple problem illustrating 
their use. 
In running a section line due north, the surveyor comes 
to a lake shore. Setting there a post, duly marked, he runs 
round the lake near the shore by the following courses: 
N 50° E 12 chains. 
N 9° 30' E 20 
N 40° W 9 
S 80° W 6.81 “ 
Reckoning up his courses by the traverse table, he finds 
