[Talk-us-massachusetts] Town boundaries redux - was Re: Talk-us-massachusetts Digest,

[Bill Ricker]

> Anyway, the best (and most fascinating) “data” regarding town boundaries
> is the https://archives.lib.state.ma.us/handle/2452/47855 Atlases created
> by the Harbor and Lands Cmsn around 1900. They are the original statewide
> surveys of town boundaries
>

Those ATLASes are good reading.
They are the Bible for the circumambulate the bounds exercise for each
town/city.
I've downloaded a bunch of them.


Warning on data: the latitude longitude and state X-Y posits listed in
those were referenced to an antique geode and datum and can NOT be directly
used. AFAIK.

 (If Paul @ MassGIS or anyone else has proj4 or similar definitions of the
old geode / datum /  coordinate systems in the Atlases, that would be
wonderful to facilitate direct use. I tried to reverse engineer based on
X-Y being statehouse cupola centered and it didn't work well IIRC. If we
had a transform(s), it might be practical to georeference the plates as
layers for our editors or Grass/QGis??)

Mass DOT has a public GIS website that has town corners as a layer (in
addition to USGS and Mass geodetic disks/monuments) with modern GEODE/DATUM
posits. The atlas will explain more but this gives the modern GPS posit if
you want to find it. IDK the license status of that data wrto OSM, but
should be usable for QA/QC.

 (I've done some fudging deriving an ad hoc affine transform between DOT
corner posits and the Atlas, in order to transform Atlas points not in any
modern registry in Middlesx Fells, assuming it's smooth. At some point I
will venture over to the State Archives to inspect the original survey of
the Fells, having been granted referral from the DCR/MDC archivist who sent
them. Much geonerdery fun there, but not directly relevant to OSM, starting
with the "MIT Geodetic Observatory". Which we should present at a mapup or
virtual mapup sometime!)

*Paul Nutting ** |**  Outreach Coordinator-MassGIS*
>

Oh cool. That would be who I need to discuss the Fells geodetic points that
got merged or lost in the state and federal catalogs during digitization. (
I think we've met at either at a mapup or a Suffolk Co political event.)

// Bill in Boston
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