34 A MANUAL FOR NORTHERN WOODSMEN 
the distribution. In any case the correction is applied so 
as to help close the survey and not the reverse. This pro¬ 
cess is called Balancing a Survey. 
The field notes of a closed survey, the latitudes and de¬ 
partures as they reckon out, and the same balanced, are 
given herewith. The reckoning is also given, and all is in 
convenient arrangement. The latitudes and departures 
COMPUTING LATITUDES AND DEPARTURES 
Course. 
Course. 
Course. 
Course. 
Course. 
A —B 
B—C 
C —D 
D — E 
E —A 
log sin = 
9.9386 
9.7604 
9.5340 
9.9555 
9.5163 
log dist. = 
1.3010 
1.1790 
1.0910 
1.2109’ 
1.3444 
log dep. = 
1.2396 
0.9394 
0.6250 
1.1664 
0.8607 
Departure = 
17.36 
8.70 
4.22 
14.67 
7.26 
log cos = 
9.6957 
9.9125 
9.9730 
9.6340 
9.9752 
log dist. = 
1.3010 
1.1790 
1.0910 
1.2109 
1.3444 
log lat. = 
0.9967 
1.0915 
1.0640 
0.8449 
1.3196 
Latitude = 
9.92 
12.35 
11.59 
7.00 
20.87 
in this case have been reckoned out not from the traverse 
table, but from the table of logarithmic sines and cosines. 
A little consideration shows that the latitude of a course is 
the cosine of its bearing multiplied by its distance, while 
the departure is the product of the sine multiplied by the 
distance. Now a table of sines and cosines gives values 
to single minutes instead of for 15' bearings. Logarithmic 
computation, too, shortens the process. This is, therefore, 
the more convenient way of reckoning for transit work, or 
for accurate compass surveying. 
When all but the final course has been run, it is in 
some circumstances desirable to ascertain what course 
to set in order to hit the starting point. This, too, may 
readily be done by means of the figured latitudes and 
departures. 
Thus, suppose that four courses of the above survey have 
