630 The Account of a 



Pilsden - - 152 37' ^',25 



Black Down - 13 37 50 ,5 



Dumpdon - - 13 44 45 &5 

 But this side may be also found, by computing with the whole 

 angle at Charton Common, which angle, when reduced to the 

 plane of the chords, becomes 141 33' 53", 75. The two sides 

 are 581012,5 feet, and 103345 feet; which data give the fol- 

 lowing triangle : 



Charton - - 141 33' 53^,5 



Dumpdon - 24 48 39 ,25 



Black Down - 13 37 27 ,25; from whence we 

 find the distance from Dumpdon to Black Down = 153094,6 

 feet. Wherefore, the mean, 153095,2 feet, maybe considered 

 to be very nearly the true distance. 



In the Lth triangle, (Cawsand Beacon, Dumpdon, and Little 

 Haldon ) the angle at Cawsand Beacon is 43 14' 2i",25; and 

 in the List, (Rippin Tor, Cawsand Beacon, and Little Haldon) 

 the angle at the same station is 25 30' 39",75 ; their sum is 68° 

 45' 1", and, adding 1'' for the necessary correction, it becomes 

 68° 45' 2". Computing with this angle, and the including sides, 

 (64020,5 and 18334 feet,) we obtain the following triangle : 



Rippin Tor - - 9o°-34' 35" 



Cawsand Beacon - 68 45 2 



Dumpdon - 20 40 23, which gives the 



distance from Dumpdon to Cawsand Beacon = 169014 feet. 



In the xLixth triangle, the observed angle at Dumpdon is 

 found to be 86° 39' 8"5, and, by adding to it the horizontal 

 angle at Dumpdon, between Rippin Tor and Little Haldon, 

 and also that between Black Down and Charton Common, we 

 get 125 54 3o",5, for the horizontal angle between Rippin 



