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Comment by wiml | Hacker News Reader

I'm not a historian of real property law, but my understanding is it's more often the other way around. The legal boundaries were/are defined by a mixture of reference to objects on the ground and conventional use. Any WGS84 coordinates you might have were non-normative. The concept of land ownership predates the concept of a single unified coordinate system by millennia.

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I assume you kind of start with boundaries defined by physical features "between this river and than hill" or similar. Then you get a secondary level defined based on this. So "X meters from the top of this hill".

And I assume now property boundaries are kind of based on a mixture of all of this? But there's a trend toward WGS84 coordinates or similar?

I also assume along the way measurement mistakes have been reasonably common or situations where those "stable" features in the landscape turned out to be not so stable.

Resolving all these issues must be a nightmare and while I've been vaguely aware of this history of surveying it now seems like it must be quite fascinating and I should try and read more about it.

If it's the history of surveying land for land use then it starts in documented history with the Egyptians marking out growing land that floods every year and was restaked with string and sight from above the flood level monuments.

If it's cartography, the two were intertwined (with differences).

Before WGS84 there were tens of state level ellipsoids and hundreds of global datums - with more than a few readjustments on the way to global unification.

One book, of many on the cartography side is

Flattening the Earth Two Thousand Years of Map Projections - John P. Snyder

https://press.uchicago.edu/ucp/books/book/chicago/F/bo363285...

who formulated the sinusoidal US space projection seen in war room move scenes showing global maps with S tracks across them for satellite paths.

On the dull and technical side (a lot of truncated Taylor series and a couple of projections using <gasp!> complex numbers) see:

Map projections: A working manual - also Snyder (free download for PDF & wallchart)

https://pubs.usgs.gov/publication/pp1395

Fun fact, we actually use the NAD83 coordinate reference system (CRS) in North America. This is a plate fixed CRS, that kind of mostly can map to WGS84, but will be different in places due to continental drift and other factors.

Here's my actual parcel description:

All that certain lot, piece or parcel of land situate, lying and being on the southeastern side of the XXX Road, in AREA NAME, in the Parish of PARISH, in the County of COUNTY and Province of New Brunswick bounded and more particularly described as follows:

Beginning at a point on the southeastern boundary of a Crown Reserved Road known as the XXX Road; said point of beginning being located at a distance of ONE DISTANCE NUMBER (###) metres measured southwesterly along the southeastern boundary of the XXX Road from its intersection with the southwestern boundary of the OTHER PROPERTY OWNER NAME property by document number ##### registered in the COUNTY County Registry Office in book ### at page ###; said boundary being the southwestern grant line of Lot # originally granted by the Crown to PERSON NAME.

Thence in a southwesterly direction following the southeastern boundary of the XXX Road a distance of ONE DISTANCE NUMBER (###) metres to a point at a corner at the intersection of the northeastern boundary of the PROPERTY OWNER NAME property by transfer number ###### registered in Land Titles for the District of New Brunswick on DATE.

Thence in a southeasterly direction parallel to the southwestern grant line of Lot #, the OTHER PROPERTY OWNER NAME property following the northeastern boundary of the PROPERTY OWNER NAME property a distance of THREE DISTANCE NUMBER (###) metres to a point at a corner.

Thence in a northeasterly direction on a line parallel to the southeastern boundary of the XXX Road a distance of ONE DISTANCE NUMBER (###) metres to a point at a corner.

Thence in a northwesterly direction parallel to the southwestern grant line of Lot X, the OTHER PROPERTY OWNER NAME property a distance of THREE DISTANCE NUMBER (###) metres to the point of beginning.

The so-described parcel of land contains an area of SOME (###) hectares more or less and is located in Lot # originally granted by the Crown to AN ORIGINAL OWNER.

BEING the same lands and premises (PARCEL NAME) conveyed to LTD CORP by Transfer duly registered at the Provincial Land Registration Office in the District of New Brunswick on DATE, as number #######.

Fascinating, thank you!

I find it interesting that the boundaries are defined by a combination of physical land features and other property boundaries.

I guess this means that there's the error could potentially accumulate when you reference against property boundaries. Then you come up against some physical reference and have to resolve the inconsistency somehow.

And on top of the fact that a lot of boundaries outside the city have been low resolution for a long time (land grants may have been from like.. 1902 for some farmer with 400 acres, and then just parceled over time with no further survey). The fact that I shifted everyone 140' by pinning my one line shows how it can be, and I'd bet there are areas that are worse because they're less developed / further out / nobody cared to ask).

TBH, looking into the history of surveying in the US is fascinating. The level of accuracy they were able to achieve over such long distances so long ago is awesome. I fell deep down this rabbit hole when I started flying a LIADR unit on a drone and working with PLS.

Much of your local mapping is based on monuments and triangulation to those monuments. The fact that the monuments are now frequently stable GNSS base stations helps tie everything together.

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