the \ Trigonometrical Operation . ri j 
above low water at fpring tides, is neverthelefs furrounded oti 
the land fide with eminences, at the diftance of fix or feven 
miles, ftill higher than itfelf. From this circumftance we 
found it impoffible to connect it with the great triangles to the 
weftward, otherwife than by a fhort fide. It was therefore 
fufficiently obvious, that it would be eligible to make obferva- 
tions of the pole ftar for determining the difference of lon- 
gitude, and the convergence of the meridians, at fome other 
intermediate ftations between Greenwich and Dover, from 
whence our longeft fides could be diftinftly feen. For this 
purpofe none Teemed fo proper as Botley Hill, Goudhurft, and 
Folkftone Turnpike. The firft of thefe three is only 171 § feet 
eaftward from the meridian of Greenwich, Goudhurft is about 
23 miles fouth-eaftward from the former, and Folkftone Turn- 
pike, the ftation neareft to Dover, is fo fituated, that from it 
can be feen the end of the bafe of verification at High Nook, 
Fairlight Down, and other diftant ftations. 
With this objedt in view, whereon fo much depended, we 
had again the mortification to be thrown into the latter feafon 
of 1788. 
Befides a better level for the axis of the telefcope, the mi- 
crofcope B wanted to be better fupported. Another fort of 
clamp, alfo an eye-piece, with a diagonal prifm for obferva- 
tions near the zenith, or for thofe of the pole ftar in higho 
latitudes, were neceffary improvements, which might have 
been executed in a fhort fpace of time. With thefe altera-- 
tions the inftrument was at laft returned, but fo late, that it 
could not be placed on Goudhurft Steeple till the 9th of. Au-- 
guft, 1788. 
The obfervations at Goudhurft, Frant, Botley Hill, and 
Folkftone Turnpike, having been finilhed early in September,. 
j ' the 
