of a Base Line on the Coast of Coromandel. 107 
It is immaterial at which end of the base line w T e begin. In 
the present case, in order to obtain as great precision as possible, 
the intermediate angles have been deduced from both ends ; 
those at A and B, from the observation at N ; and the remain- 
ing ones at C D and E, from that at S. Had, however, this 
precaution been neglected, the error induced, by deriving the 
four required angles from either primitive, at N or S, would 
not have affected the true length of the whole base line more 
than 0,27 of a foot, or not quite so much as three inches and 
a quarter. 
This method of obtaining the measure of an inaccessible 
line, where the measured lines every where make small angles 
with it, is a very accurate one ; for though, in oblique triangles, 
small angles, from the difficulty of taking angles perfectly, are 
likely to produce considerable errors, in right-angled triangles 
it is the very reverse ; as in them the smaller the angle taken, 
the more accurate will be the result. 
Fig. 1. is not drawn in due proportion, either as to the sides 
or angles; as, had it been justly delineated, there would not 
have been sufficient room for the auxiliary lines, and letters of 
reference. Fig. 2. is protracted by scale and sector, and shews 
the relative length and bearing of the several measured lines, 
as well as the direct distance of their farthest extremities, and 
their position with respect to the meridian. 
For distinction sake, the measured hypothenusal lines are 
drawn thicker than those about them ; and the lines which are 
parallels to the base line are dotted. 
P 2 
