>
>Metes and bounds encompasses a heck of a lot more than bearings and
>distances in surveyors terms, does it not? A quick look on the web agrees
>with what I've always thought of m&b - as descriptions from trees, rocks,
>creeks, other folk's properties, etc., most of which have long
>disappeared. A real nightmare on the east coast. Don't know how you'd do
>any of that in mapinfo. Glad I don't have to deal with it. :-)
Hi Mark:
I think you east-coasters (USA) have it tougher than we do out here in the
west. The Public Land Survey, despite it's many problems (especially in
Indian Country) was done recently enough that one can still find remnants,
or surveys from the 1920's-onward that indicate what original Public Land
Survey evidence they found. I've been known to go out and use
differentially-corrected GPS to locate a found starting point, and work
from that (realizing the errors involved). But there are many problems. We
don't attempt to DO a survey, just re-create for illustrative purposes a
survey already completed. Often having re-created it in MapInfo I can go
out in the field with a differentially-corrected GPS plugged into a laptop
running MapInfo and GeoTracker, with my COGOline-'ed result guiding me
on-screen, an aerial orthoimage for context - when I'm within about 20 feet
of a corner that's been surveyed in the last 30 years there's usually
enough evidence to find the surveyor's flagging, pin or post. Sometimes
not, but it's the best we can do.
Washington State Law dictates that surveys since 1972 be recorded with the
County Recorder, and our county has scanned all those surveys as TIFF's and
put them on a series of CD's for distribution, so we can quickly print out
any recent-ish survey on the Laserjet and take that out in the field as
well. It helps. The county provides a Shapefile point file that indicates
which volume and pagenumber the survey is - and of course we view that in
MapInfo.
We found out about the survey CD's, along with much other data, from
attending local user groups and shmoozing with our peers in local
government. Never underestimate the power of networking! We believe in it
so much we're running the group (and another one) ourselves now.
MapInfo would be quite inadequate for a surveyor (my opinion) - but for our
purposes it's really awfully good. Doug Pease was good enough to recommend
COGOpoly.MBX from the directionsmag.com site - that should enhance
MapInfo's capability to do this sort of work.
Tom
* - * - * - * - *
Tom Curley
Suquamish Tribe GIS Program Manager
[EMAIL PROTECTED]
1.360.394.5337
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