[time-nuts] Latitude and longitude question

[John Pettitt]

Joseph Gray wrote:
> Let me first say that I don't know anything about surveying. I have a copy
> of the plat survey for my house. On the survey are four sets of coordinates
> that resemble lat/long numbers, but obviously aren't. What are these
> coordinates and is there any way to calculate a lat/long of a specific point
> on my property from these numbers? If so, how accurate could I expect the
> result to be? I assume that a professional survey should be highly accurate.
>
> Any pointers to information on doing this would be appreciated.
>   
Where are you?   Some countries (for example the UK) have their own grid
system.  A survey should be accurate to around 20mm +/- 50ppm - see
http://www.acsm.net/alta99.pdf

John