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holograph

Transcontinental Triangulation

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I've been doing some research on the Transcontinental Triangulation, the first coast-to-coast network in the U.S. There were recent threads in this forum touching upon portions of the network, specifically the Davidson Quadrilaterals in California and the Great Hexagon of Nevada and Utah.

 

I decided to find the locations of the stations of the entire network and cross reference them to the PIDs in today's database. I've begun putting some results on the Benchmark Wiki site. The complete nework is briefly described in an overview page. The first detailed page that has been created is the Eastern Shore series page.

 

It's been fascinating to learn how the stations were established and used, and the historical context of some of the stations that we can still find today.

 

Of couse, no Wiki can ever be considered complete. You are all welcome to add information as you see fit. Come visit and help make the site better!

 

overview_th.jpg

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I too have been doing research into this.

 

I will try to go over the data I have and post what does not appear in your list.

 

Thanks for another great project.

 

So Far.

What I have studied this started at Cape Hatteras Light House

EX0345

CAPE HATTERAS LH 1933

In DARE county, NC

http://www.geocaching.com/mark/details.aspx?PID=EX0345

 

and went to The Light House at Point Reyes

HT3489

POINT REYES LIGHTHOUSE 1870

In MARIN county, CA

http://www.geocaching.com/mark/details.aspx?PID=HT3489

 

or it may have been

JT2885

POINT ARENA LH SPIRE 1930

In MENDOCINO county, CA

http://www.geocaching.com/mark/details.aspx?PID=JT2885

 

I will have to look to make sure.

 

I think this Pricipio and Turkey point are the ones mentioned in that article.

JV4789

PRICIPIO 2

In CECIL county, MD

http://www.geocaching.com/mark/details.aspx?PID=JV4789

 

JV4850

TURKEY POINT RESET

In CECIL county, MD

http://www.geocaching.com/mark/details.aspx?PID=JV4850

 

Here are some connected to the 98th Meridian as well.

JG0687

NORTH SHERMAN CAIRN 1899

In ELLSWORTH county, KS

http://www.geocaching.com/mark/details.aspx?PID=JG0687

 

JG0689

TABLE MOUNTAIN CAIRN 1899

In ELLSWORTH county, KS

http://www.geocaching.com/mark/details.aspx?PID=JG0689

 

JF1632

SHERMAN 1899

In ELLSWORTH county, KS

http://www.geocaching.com/mark/details.aspx?PID=JF1632

 

GH0874

KANSAS OK BDRY STONE 160 1902

In HARPER county, KS

http://www.geocaching.com/mark/details.aspx?PID=GH0874

 

JG0683

TURKEY POINT 1891

In LINCOLN county, KS

http://www.geocaching.com/mark/details.aspx?PID=JG0683

 

KL0637

MOUNT ELBERT

In LAKE county, CO

http://www.geocaching.com/mark/details.aspx?PID=KL0637

 

Reference Points for above.

JL0654

BUFFALO PEAK

http://www.ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=JL0654

N 38 59.50667 W 106 07.50500

N 38 59 30.4, W 106 07 30.3

 

JL0664

MOUNT HARVARD CAIRN

http://www.geocaching.com/mark/details.aspx?PID=JL0664

 

JL0665

MOUNT YALE

http://www.ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=JL0665

N 38 50.65167 W 106 18.82833

N 38 50 39.1, W 106 18 49.7

 

KL0688

CAPITOL PEAK

http://www.geocaching.com/mark/details.aspx?PID=KL0688

 

KL0640

MOUNT MASSIVE CAIRN

http://www.geocaching.com/mark/details.aspx?PID=KL0640

KL0647

MOUNT OF THE HOLY CROSS CAIRN

http://www.geocaching.com/mark/details.aspx?PID=KL0647

 

KL0638

GALENA MOUNTIAN

http://www.ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=KL0638

N 39 14.50833 W 106 27.38667

N 39 14 30.5, W 106 27 23.2

 

KL0638

MOUNT GALENA

 

KL0689

TREASURY MOUNTAIN LAT STA

In GUNNISON county, CO

http://www.geocaching.com/mark/details.aspx?PID=KL0689

 

JL0797

UNCOMPAHGRE LAT STA CENTER

In HINSDALE county, CO

http://www.photolib.noaa.gov/historic/c&gs/theb2566.htm

 

http://www.geocaching.com/mark/details.aspx?PID=JL0797

 

JL0798

UNCOMPAHGRE

In HINSDALE county, CO

http://www.geocaching.com/mark/details.aspx?PID=JL0798

 

I am still working on them and will try to update more soon.

Edited by GEO*Trailblazer 1

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There were several different 19th century triangulations. There is the Eastern Oblique Arc, which went from Calais Maine to New Orleans. It was done over a period of time between the 1840's and 1900. It wasn't a single project, but it was nearly as important.

 

The 98th meridian arc was commenced specifically to run a north-south triangulation that tied into the Transcontinental arc. It was done in the early 1900's. By then technology was allowing faster progress. Ultimately the 98th meridian arc was extended into Canada and Mexico and provided the means to establish a North American datum, NAD27.

 

The Transcontinental Triangulation was specifically along the 39th parallel. It wouldn't have included anything from North Carolina, but I'm sure there were other triangulation projects that did extend down the coast. Some of the very first triangulation networks in America were done along the coast. There was also quite a bit of activity on the West coast in California prior to the Transcontinental Triangulation, and the west coast network was eventually extended to Washington state.

 

I've based my maps and lists on the 1900 report of the Transcontinental Triangulation published by the CGS. I was fortunate enough to obtain a copy of that report. There is also a published report for the Eastern Oblique Arc, but it is too expensive for my budget, and I don't have ready access to a library which may have a copy. :(

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I signed up.

 

Now I would like to ask if it is ok to try and add some of the marks I have found for the Baselines you have.

 

I have found quite a few of the Baselines and corresponding marks.

 

I will have to do some studying to get the thing right.

I have worked some on another wiki.

 

If you would rather me post it here let me know that too no problem.

 

Thanks

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holograph,

 

You are just too awesome.

I do not know how you do it so fast.

 

I am a piddle in a bucket compared to you at this.

 

Thanks again for all the updates.

I am still searching the holes (you probably) left on purpose across Missouri.

I have found several that match the dates you have on the ones listed.

 

I am still filling in my dinky base and will find others as I research.

I will try to add them.

 

Thanks again.

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What I did with the Transcontinental report was obtain the list of all stations, then all the triangles so I could plot the lines between stations. For each station, I also noted the year observations were taken. I also used the line lengths in some cases to locate stations when I could not easily find a corresponding datasheet.

 

That would be a lot of work (it was a LOT of work for the Transcontinental arc!). However, for the Eastern Oblique arc, I already have the following sections, obtained from the CGS annual reports:

 

Epping, Mass to Fire Island, NY (1865 pg.197)

New York to the District of Columbia (1866 pg.52)

Kent Island to Atlanta (1878 pg.94)

 

What's missing are the stations and triangles from Calais, ME to Epping, MA, and from Atlanta to New Orleans.

 

Any information you can provide would be greatly appreciated. Thanks.

Edited by holograph

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So I went to the library today, and once I got there I realized I had pretty much no idea what would be useful. So I started taking photos. All in all, I have about 60 pages of the text captured.

 

Here's one of the charts from in back.

 

Here's a list I created:

Astronomic Latitude Observed Longitude

1 Calais, ME 45°11'09.40" ±0.06" 67°16'57.86" ±0.75"

2 Cooper, ME 44°59'12.60" ±0.05"

3 Humpback, ME 44°51'47.56" ±0.05"

4 Bangor, ME 44°48'12.87" ±0.05" 68°47'02.60" ±0.78"

5 Farmington, ME 44°40'19.54" ±0.05"

6 Mount Harris, ME 44°39'54.66" ±0.04"

7 Howard, ME 44°37'49.24" ±0.05"

8 Mount Desert, ME 44°21'06.51" ±0.03"

9 Ragged Mountain, ME 44°12'42.96" ±0.04"

10 Sabattus, ME 44°08'37.73" ±0.09"

11 Mount Pleasant, ME 44°01'36.44" ±0.04"

12 Cape Small, ME 43°46'43.69" ±0.04"

13 Mount Independence, ME 43°45'34.47" ±0.06"

14 Gunstock, NH 43°31'03.81" ±0.05"

15 Agamenticus, ME 43°13'24.96" ±0.06"

16 Isles of Shoals, ME 42°59'12.97" ±0.09"

17 Unkonoonuc, NH 42°58'59.34" ±0.07"

18 Thompson, MA 42°36'38.02" ±0.10"

19 Wachusett, MA 42°29'16.13" ±0.04"

20 Cambridge, MA (Harvard Observatory) 42°22'48.05" ±0.22" 71°07'45.69" ±0.75"

21 Cambridge, MA (Cloverden Observatory) 42°22'40.97" ±0.08"

22 Mount Tom, MA 42°14'27.62" ±0.06"

23 Manomet, MA 41°55'35.35" ±0.05"

24 Sandford, CT 41°27'40.47" ±0.08"

25 West Hills, NY 40°48'50.06" ±0.04"

26 New York, NY 40°43'48.39" ±0.09"

27 Beacon Hill, NJ 40°22'27.81" ±0.07"

28 Mount Rose, NJ 40°22'05.41" ±0.08"

29 Yard, PA 39°58'29.39" ±0.06"

30 Principio, MD 39°35'32.81" ±0.04"

31 Maryland Heights, MD 39°20'32.10" ±0.04"

32 Pooles Island, MD 39°17'17.52" ±0.15"

33 Sugar Loaf, MD 39°15'49.71" ±0.10"

34 Dover, DE 39°09'13.62" ±0.06" 75°31'18.45" ±0.79"

35 Webb, MD 39°05'25.21" ±0.04"

36 Soper, MD 39°05'10.69" ±0.09"

37 Rockville, MD 39°05'10.45" ±0.03"

38 Taylor, MD 38°59'46.08" ±0.12"

39 Strasburg, VA 38°59'31.49" ±0.09" 78°21'35.70" ±0.80"

40 Cape May, NJ 38°55'44.74" ±0.06" 74°55'45.68" ±0.75"

41 Causten, DC 38°55'32.18" ±0.06"

42 Old Naval Observatory, DC [1] 38°55'13.91" ±0.06" 77°03'02.30" ±0.75"

43 Hill, MD 38°53'52.31" ±0.05"

44 New Naval Observatory, DC [2] 38°53'38.79" ±0.03" 77°03'56.76" ±0.78"

45 Seaton, DC 38°53'25.20" ±0.15" 76°59'52.73" ±0.78"

46 C&GS Office, DC [3] 38°53'07.43" ±0.02" 77°00'25.64" ±0.78"

47 Bull Run, VA 38°52'56.79" ±0.07"

48 Marriott, MD 38°52'25.12" ±0.06"

49 Cape Henlopen, DE 38°46'40.00" ±0.05"

50 Clark, VA 38°18'39.80" ±0.06"

51 Elliott Knob, VA 38°09'57.51" ±0.11"

52 Charlottesville, VA 38°02'00.95" ±0.14" 78°31'20.10" ±0.80"

53 Long Mountain, VA 37°17'28.72" ±0.09"

54 Moore, NC 36°23'54.95" ±0.09"

55 Young, NC 35°44'21.50" ±0.12"

56 King, NC 35°12'13.31" ±0.07"

57 Paris, SC 34°56'31.96" ±0.07"

58 Currahee, GA 34°31'37.75" ±0.08"

59 Lavender, GA 34°19'15.81" ±0.12"

60 Sawnee, GA 34°14'04.20" ±0.08"

61 Aurora, AL 34°08'47.45" ±0.12"

62 Atlanta Middle Base, GA 33°54'21.82" ±0.05"

63 Atlanta, GA 33°44'59.30" ±0.12" 84°23'20.07" ±0.80"

64 Kahatchee, AL 33°13'39.90" ±0.06"

65 Montgomery, AL 32°22'45.41" ±0.04" 86°17'59.19" ±1.1"

66 Lower Peach Tree, AL 31°50'21.19" ±0.10" 87°32'40.94" ±1.1"

67 Coon, AL 31°14'47.82" ±0.05"

68 Mobile, AL 30°41'33.42" ±0.06" 88°02'37.37" ±1.0"

69 East Pascagoula, MS 30°20'40.92" ±0.04"

70 Fort Morgan, AL 30°13'47.89" ±0.03"

71 New Orleans, LA 29°57'25.28" ±0.07" 90°04'11.44" ±0.80"

XX Petersburg, Roslyn Station, VA 77°23'46.61" ±0.84"

YY Wilmington, De Rosset Station, NC 77°56'36.72" ±1.0"

ZZ Raleign, State House Grounds, NC 78°38'05.30" ±1.0"

AA Charleston, Citadel Square, SC 79°56'01.14" ±0.78"

BB Statesville, near Simenton College, NC[4] 80°53'41.31" ±0.80"

CC Columbia, Capitol Square, SC 81°02'02.70" ±1.2"

DD Macon, Academy Square, GA 83°37'35.70" ±1.3"

 

[1]Center of clock-room

[2]Center of small dome

[3]Station in yard

[4]Latitude too?

 

I also have a bunch of pages with titles like:

  • C. Resulting geographic positions of the principal stations of the triangulation between Calais, Maine, and New Orleans, Louisiana, based upon the Clarke Spheroid of 1866 and the data of the transcontinental triangulation.
  • D. Additional geographic positions of astronomic stations for which triangles are not given in this paper and which were derived differentially.
  • E. Additional geodetic azimuths computed directly from the given positions of two stations.
  • Resulting angles and sides of the Epping base net, Maine.
  • Resulting angles and sides of the fifth and last section of the triangulation west of the Atlanta base net.
  • Abstracts of horizontal directions at stations of the first section of the triangulation west of Dauphin Island base net.
  • Resulting angles and sides of the triangulation west of Dauphin Island base net.
  • Resulting angles and sides of the second and last section of the triangulation west of Dauphin Island base net.
  • Summary of results for latitude (astronomical)
  • Summary of results for longitude
  • Comparison of astronomic and geodetic latitude.
  • Comparison of astronomic and standard geodetic longitude.
  • Comparison of astronomic and geodetic azimuths of the sides of the triangulation.
  • Resulting angles and sides of the triangulation between the Epping base net and the northeastern terminus of the arc.

I also took pictures of all the net diagrams (the ones I think look like connect-the-dots). Can any of this help?

 

SLer

Edited by Shorelander

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What an interesting project. I find the historical aspect of this hobby to be the best.

 

I wish I had the time to do this kind of research.

 

Can I suggest if you can find a copy to take a look at Special Pub No. 110 “Astronomic Determinations” by Sarah Beall. It has a lot of information on the astronomic stations which where often identical with the triangulation stations. And includes descriptions.

 

For instance:

Calais longitude Edwin Goodfellow 1857)

“ Identical with the triangulation station Calais Observatory, which is south of the Calais High School and near the center of the school ground bounded on the northwest by North Street and on the northeast by Academy Street. The station is at the most elevated point in Calais and is marked by a rough granite block smoothed at the top and south side.

 

Calais latitude (Washington County, ME G.W. Dean, 1857)

Marked by a granite column 0.193 meter or 0”.01 of latitude north and 1.594 meters west of Calais longitude described above.

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Yes, fascinating! I thought I would be pretty much out of it down here in the far corner of the country (SoCal), but it turns out that I HAVE recovered one of the "Western or Coast Range Series", Mount Saint Helena, in Sonoma County, in Northern CA, JT2703 back in 2003 (and logged with NGS - I'm LJK). Neat!

Edited by Klemmer & TeddyBearMama

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Another interesting thing about Calais is that it was one of the first points that longitude was determined by telegraph, since it was one of the closest geodetic stations to the end of the first transatlantic telegraph. The telegraph was used to exchange time signals with Greenwich. From Calais, longitude (i.e. time) was transfered by telegraph to Harvard observatory in Boston, and eventually to the Naval Observatory in DC. For a period of time, all longitudes in the U.S. were referenced to the Harvard observatory in Boston.

 

The telegraphic longitudes were a huge improvement over longitudes determined from chronometer exchanges.

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Can you tell us more about using the telegraphic time signals? It seems hard to imagine that even with a two-way transfer to measure the path delay, there had to be a human reading the astronomical position and thus a tenth second or so of uncertainty. Then 0.1 second time * 360 deg/24 hours = 1.5 seconds of longitude, and Wheeler was recording x.xx second precision. What don't I understand?

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In general, they used precision chart recorders and precision glass reticules to read the charts. A second was represented 3/4 to 1 inch on the chart, and it was possible for a skilled operator to read to the nearest hundreth of a second.

 

The time signals were automatically generated by astronomical clocks. Surveyors had already learned to determine the instant a star passed a meridian telescope, and they recorded those instants in the telegraphic signal, also.

 

By that means, it was possible to determine the difference in time to about 1/100 second, which translates to about 0.15 second of longitude. At a latitude of 40°, that's about 3.5 meters.

 

The transatlantic exchange of time required slightly different technique because the signal strength was so weak. The signal was detected by sensitive galvanometers. It was found that an operator was remarkably consistent in the amount of error he introduced in reading the instruments, and it was possible to compute a "pesonal equation" that accounted for a particular operator's error.

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As the old commercial said "We've come a log way, baby!".

Can you imagine what one of those folks from the late 1800's or so would think of GPS?

 

edited speeeling

Edited by Klemmer & TeddyBearMama

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In general, they used precision chart recorders and precision glass reticules to read the charts. A second was represented 3/4 to 1 inch on the chart, and it was possible for a skilled operator to read to the nearest hundreth of a second.

 

The time signals were automatically generated by astronomical clocks. Surveyors had already learned to determine the instant a star passed a meridian telescope, and they recorded those instants in the telegraphic signal, also.

 

By that means, it was possible to determine the difference in time to about 1/100 second, which translates to about 0.15 second of longitude. At a latitude of 40°, that's about 3.5 meters.

 

The transatlantic exchange of time required slightly different technique because the signal strength was so weak. The signal was detected by sensitive galvanometers. It was found that an operator was remarkably consistent in the amount of error he introduced in reading the instruments, and it was possible to compute a "pesonal equation" that accounted for a particular operator's error.

 

I’m always amazed at the highly complex mechanical devices that were available in the 18th and 19th centuries. We know there were striking clocks (clocks that sound a bell on the hour or more often). So it is not much of a stretch of the imagination that a precision clock with a precision “striking” mechanism be hooked up to a telegraph key.

 

Because of the resistance of the wire there was always a loss of “signal” over any distance, so every so many miles there was a relay to boost the signal. Since surveyors were accustom to closing their work, again it is not a big stretch of the imagination that they rigged a device to send the signal back to its origin where they checked the time difference between the sent and received signals and telegraphed that information to the field station which in turn used that to make their adjustments.

 

This is all conjecture on my part, so there could have been a much more accurate method used. And this is not to refute anything Holograph said.

 

Still a fascinating subject.

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Well I am benchmarking 500 right now.

Went for 4 of the Transcontinental Arc marks while attending the Big Lewis and Clark Event at the Conflunce with Destiny in St. Louis this weekend.

 

I recovered

JC1600 INSANE ASYLUM

EDITED: THIS APPEARS TO BE THE FIRST GEOCAC/NGS RECOVERY SINCE 1871.

 

JC1704 HALLECK RESET

 

I could not find this one due to recent septic or water line installation at coordinates.

JC1664 PATTERSON

 

I could not locate a safe way in to this one.

The lightning,rain and tornado threat was too close to get out a trek up there.

JC1670 LYNCH 2

 

We had a blast and I guess this will be my next project getting a few more of these across Missouri.

 

Let's see how my average turns out.

Edited by GEO*Trailblazer 1

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