iierved with the aft.j 
[quadrant in 1783. 
258 
• Gen . Roy's Account of 
1 
N° 
Triangles. 
\ 
Angles. 
Diftances of the ftations from 1 
the interfered object in feet. 
t 
\ 
f ;Tew’s Harp ftation 
0 / // 
4 4 1 45 
1 from St. Fancras f 
5728.1 
■w. 
37 - ■ 
2 (Black Lane ftation 
l_iS U. Pane* as Cbnrcb 
12 58 25 
l62 I9 5O 
j _ Church 1 
. 
2088.8 
That thefe fecondary triangles may be more generally ufeful 
to the inhabitants of London and its environs, the angles, 
which the 53 points comprehended in Plate XI. refpe&ively 
form with each other at the center of the dome of St. Paul’s, 
are colleded in the annexed table, together with their feveral 
diftances from that central point. The objedts are arranged 
into two claffes, according as they are fituated to the eaftward 
or weft ward of the meridian of St. Paul s. Thofe of the 
firft clafs commence at the north meridian, and proceed by the 
eaft to 180°. Thefe of the fecond commence at the fouth 
meridian, and^proceed, in like manner, by the weft to 1S0 0 . 
From this table the total angle between any two objedls being 
had by fimple fubtradlion, and the diftances from St. Paul’s 
given, the diftances of the objedls from each other are readily 
obtained. Whoever, therefore, fhould be defirous of know- 
ing accurately his own fituation in this great metropolis may 
eafily fatisfy himfelf, by taking two angles from the top of 
his houfe, with a good Hadley’s fextant or theodelet, be- 
tween any known objedls near to him, and thebeft dilpofed for 
the purpofe. By the help of thefe data , and a very fimple trigo- 
nometrical computation, he will obtain what he wants ; and he 
may even fatisfy another curiofity which will probably occur, 
namely, that of putting to the teft: our original operation, by 
trying how nearly different triangles bring out the fame refult. 
It will readily be conceived that, for trials of this fort, the 
l points 
