Trigonometrical Survey. 511 
No. of 
triangles. 
Names of stations. 
Observed 
angles. 
Diff. 
Spheri- 
cal 
excess. 
Error. 
Angles corrected 
for calculation. 
XU. 
Eeachy Head 
Rook’s Hill - 
Dunnose 
0 / n 
20 46 53 
122 59 14,5 
3 6 *3 5 8 
— 0,2 
- 7>7 
+ i>i 7 
" 
ft 
20 46 52,75 
122 59 8 
3 6 *3 59 j2 5 
0 
0 
00 
6,77 
- 1,27 
XLII. 
Dunnose 
Chanctonbury Ring 
Beachy Head 
20 30 58 
i 3 ° 59 37 >7 5 
28 29 30 
+ 0,86 
- 8,77 
+ 1,92 
20 30 58,75 
130 59 29 
28 29 32,25 
180 . 0 5,75 
6,01 
— 0,26 
give the four distances of'Beachy Head from Dunnose, as be- 
neath ; 
339394’ 
339395 ’° l feet 
339399’ 2 | 
3394 Q1 ’5J 
Hence 33939796, the mean, may be considered as very nearty 
the true distance. 
In the correction of the angles of the triangles which com- 
pose this branch, we have been a little more particular than 
with the others of the series, as it is of much consequence that 
the distance between Beachy'Head and Dunnose should not 
be left doubtful. 
In the 42d triangle, it must be observed, that there is a de- 
fect of nearly in the sum of the observed angles ; in the 
38th, about \ a second ; and in the 41st, a defect of about 
1"^: the sum in the 39th is nearly right, but the angles of it 
are considered as residuary, or remaining angles ; the triangle 
being too oblique to be admitted as a principal one in the 
series, though numbered and inserted as such. 
3U 2 
