2^2 Major-General Roy’s Account of the 
fpot would furnifh the neceflary centinels, particularly during 
the night, for guarding fuch parts of the apparatus, as it was 
forefeen muft remain carefully untouched, in the frequent in- 
terims of difcontinuing and reluming the work. Accordingly, 
a party of the 12th regiment, of foot, coillifting of a ferjeant, 
corporal, and 10 men, were ordered to march from Windfor 
to Hounfiow- Heath, where they encamped on the 26th ©f 
May, clofe by Hanworth Snmmer-houfe, to which fpot the 
neceflary tents, camp equipage, and entrenching tools, &c. 
had been previoufly fent. 
Whatever might have been the particular direction given to 
the bafe conftdered by its extremities, from confulting the plan 
it will eafily appear, that it mu ft always neceflarily lead 
through the narrow gorge of the Heath formed by Hanworth- 
Park and Hanworth-Farm. The firft point therefore to be 
attended to, in tracing it out, was, that it might lead through 
this pafs, without interfering with certain ponds, or gravel-pits 
full of water, which are in it. Thefe were eafily avoided by 
carrying the line pretty near to Hanworth Summer-houfe ; and 
in directing the telefcope from thence towards the fouth-eaft* 
it was accidentally found, that by leaving Hampton Poor- 
houfe a very little to the weftward, or right, the line would 
coincide with a remarkable high fpire, feen at the diftance of 
eleven or twelve miles, and known afterwards to be Banfted- 
Church. As there could not be a better fituated, or more 
eonfpicuous objedt than this, therefore the firft or fouth-eaft 
fedlion of the bafe, comprehended between the Summer-houfe 
and the angle of the fmall field adjoining to Hampton Poor- 
houfe, was immediately diredted upon it ; and the foldiers were 
the fame day fet to work to clear the tradt, which, at a me- 
dium, was made from two to three yards in breadth. This 
operation 
