wow glass fibre elongation measuring, thats a cable for measuring from an established point, which established point is the basis of all surveying:yawn:
For those whose basic knowledge doesn't get as far as Skybirds much broadcast "wisdom" which he has been said repeatedly for many years now, the location of the needed established point is nowadays much assisted by GPS, the avenue is not restricted to such really really difficult stuff like distance and angle from one point to another to calculate length and depth but can also be used for such complicated modern nightmares of mathmatics such as ploughing in a straight line over an undulating field.
Damn that 20th century, god knows what they will think of when we ever get to the 21st century and finally get modern technology:yeah:

Surveying is following basic principles that existed before modern records and have developed regularly, if your knowledge is derived from Google(apart from when you knew two gay men at Gymnasium which makes you somehow qualified to speak on civil partnerships) then it is no surprise that you repeatedly link to some really crazy websites that share your rather narrow views

I think we're trying to catch up to you in terms of CCTV coverage. :haha: