California Surveyors Forums

Hi all,
sometimes I like to ask the most basic of questions about why I or we, do what we do.
That being said while mapping a RoS right now I came to wonder what the real purpose of showing reference map bearings and distances underneath or alongside our field measurements, why do we do this really? I get listing all the pertinent references, that's obviously important for future surveyors and the public. And I can see why it would be helpful to show courses that my measurements disagree with, or ones that I would use to make a calculation but I have been taught that we show these courses under every field measurement on every line of the survey and have been urged to show all previous measurements ever taken. What are we really saying when we show these references?

N 0°36'23" E 549.92
O------------------------------O
(N 0°37'12" E 549.54 R)

Thanks for the enlightenment in advance,

I don't show reference dimensions unless my measurements are in disagreement.

One of the reasons is to permit a rotation to orient the two surveys. The other is it is comparable to showing record distances. By knowing the bearing rotation, you can anticipate that the rotation should be uniform throughout.

Same with the distances, Michael.

Depending upon that date of the survey and the equipment used, being able to compare the record and measured distances allow a better understanding of the footsteps of the previous surveyors. For example, learning that measurements from the 1920' are all short of what we measure might indicate a stretched tape or chain. The ratios of the dimensions can lead to some interesting observations and assist in following in those 100 year old footsteps.

Its a way for those who will follow you to better understand your survey and how it relates to the previous ones.

Thanks Jim, It seems to be something all the surveyor's do around here.
Thanks Mike, Why not rotate the reference map and state the rotation in the references so you can compare apples to apples? I guess some people do..
I feel like I've been blindly trying to show all references all the time lol.
Ian, another good one!

Yes! Thanks Ian for that comment. I also adopt these similarities when I COGO drawings for GIS. Another reason I do it, is belts and suspenders. I like redundancy checks.

I personally like using a selective choice of R&M to show my methods for each line in so as to make it easy to review/understand each lines resolution. Some other surveyor's previous measurement is just their opinion and only matters when it matters. When it matters is generally limited to the subject deed, the document that created the line in question, or when I am holding a record distance and interior angle from someone else's work to re-establish the position of a lost monument that they measured. Or when its like Ian said, and it is useful to show a bigger picture.

Mikey Mueller,
PLS 9076