A "line" is straight by definition. If a corner monument is off line, all you have to do is either dig it up and move it, or just bump it over with a hammer, depending on the monument material.
Well then, what is a curved line by definition?
Now we are talking survey stuff!;-)
Keith
East-West section lines are on a CURVED line.
oops......
East-West section lines are on a CURVED line.
...how about line of constant bearing?
East-West section lines are on a CURVED line.
You got that right!
Seems like I read that someplace......oh ya, the BLM Manual!
East-West section lines are on a CURVED line.
I will always believe that the lines withing a township were ran by determining the Declination and turning East, or West, and then following the line of sight from the location the declination was determined and recorded, not the compass. That's why the declination is only shown at the Section corners. The GLO knew there was distortion and doing it as plane surveying would create more, they limited limiting the area by correction lines correction lines so the effects would be minimual. I may be the only one in the world that believes this, that's fine, when I find at 45° North where I survey, evidence that section lines were ran on the curve I will change my mind. Haven't found evidence while retracing the GLO that would be precise enough to prove the section lines were not ran along the line of sight. Yep, we live on a globe, but intent is still a huge factor when evaluating evidence and practice. Not intending to change anyone's mind, just expressing a very unpopular opinion, I do know most do not agree with me on this.
jud
there is no such thing as a CURVED line.
At least that's what my geometry teacher taught me.
there is no such thing as a CURVED line.
Well I kinda agree with you Perry, that's why I posted about a line of constant bearing. I did look it up though. Check the second definition:
Line?[lahyn] Show IPA noun, verb, lined, lin·ing.
noun
1.
a mark or stroke long in proportion to its breadth, made with a pen, pencil, tool, etc., on a surface: a line down the middle of the page.
2.
Mathematics . a continuous extent of length, straight or curved, without breadth or thickness; the trace of a moving point.
3.
something arranged along a line, especially a straight line; a row or series: a line of trees.
4.
a number of persons standing one behind the other and waiting their turns at or for something; queue.
5.
something resembling a traced line, as a band of color, a seam, or a furrow: lines of stratification in rock.
Correct Answer: "East-West section lines are straight."
Township Lines are laid out East-West cardinal.
Section corners are set on that cardinal line.
After that each additional section is laid out with straight lines.
Unless my Manual has gross printing errors.
Paul in PA
Wow...I didn't remember starting a new thread....
> Well then, what is a curved line by definition?
>
> Now we are talking survey stuff!;-)
>
> Keith
Go get 'em.
RoadBurner
Just maybe the correct definition of a curved line is in the Manual.
See the 2009 Manual, section 3-114: ". . . In this application, "straight lines" implied "lines of constant bearing" (43 U.S.C. 752.(2))
I will go with that!
And another thing: Most of us know that many lines of the PLSS were run on the ground with a solar transit and I would like to know how an instrument straight line would have been possible with that instrument? It automatically runs a curved line, for those who don't know.
Keith
RoadBurner
> And another thing: Most of us know that many lines of the PLSS were run on the ground with a solar transit and I would like to know how an instrument straight line would have been possible with that instrument? It automatically runs a curved line, for those who don't know.
>
> Keith
So?
I run a traverse around a property, the traverse isn't the boundary.
RoadBurner
> Just maybe the correct definition of a curved line is in the Manual.
>
> See the 2009 Manual, section 3-114: ". . . In this application, "straight lines" implied "lines of constant bearing" (43 U.S.C. 752.(2))
>
> I will go with that!
>
> And another thing: Most of us know that many lines of the PLSS were run on the ground with a solar transit and I would like to know how an instrument straight line would have been possible with that instrument? It automatically runs a curved line, for those who don't know.
>
> Keith
Yup! Carlson handles that now. Awesome! 🙂
RoadBurner
I have no knowledge of Carlson of course, but that is awesome!!
Dumb Answer: "East-West section lines are straight."
Question: Have you ever retraced a PLSS section line?
Keith
3-55 in the 73 manual is describing a projected line, Township lines are to be ran using the constant bearing plan, but not interior section lines. When you can see back for miles and there are angle points at each section Corner, the reason is all the section corners were set by running North setting corners along the way from the Township line which was intended to be ran on a the true latitude. 2-75 address the E-W township lines. 3-17 is about governing lines for Townships. The interior lines of a township were intended to be completed by using Plane Surveying methods, the term projected as used in 3-47 along with the term rectangular limits I believe are speaking about straight lines. The intent was to survey the lands quickly by creating rectangular tracts and placing the expected closing discrepancy's caused by using that method combined with the narrowing of the Meridians as you go North, into the last half mile while running the lines for the North and West sections. I believe we are being to smart for our own good and have been misled, the misleading was thought to be truth, with no intent of harm. Hard to be the only one of a few to speak out about that a popular view may be in error.
jud
East-West section lines are not on a straight line.
You have to answer this then:
We know that the solar transit was the workhorse of the GLO and explain how it could run an instrument straight line through the timber and over the hills?
Obviously, we know that short cut methods were used by some and in some cases, only a half mile of east-west section lines were actually run on the ground and probably by turning 90 degrees from the north-south line.
I am looking for that sentence in the Manual where it states that east-west section lines were to be run at instrument straight lines?
But that does not explain how the solar transit worked.
East-West section lines are not on a straight line.
The solar transit I believe was a transit with a solar attachment that used the sun, time and tables to find geodetic North. When the instrument was orientated North, a 90° angle was turned to determine the direction of the latitude at the location of the instrument.
jud
East-West section lines are not on a straight line.
Not Geodetic North, ASTRONOMIC NORTH.