In going through the papers of the famous Austin surveyor and former Commissioner of the GLO, Jacob Kuechler, recently, I happened across on odd entry that had ended up in the equivalent of a "miscellaneous" file. Here is what was written on it in what appears to be Kuechler's own hand.
It's a series of magnetic declination values for various places in West Texas. My present hypothesis is that these were values observed by others that Kuechler made note of before heading out in 1878 to survey in the Texas & Pacific Railroad Company's 80-Mile Reservation West of the Pecos. The question is where these values came from. One possibility is that Kuechler took them from the report of the Clark survey of the boundary between Texas and New Mexico, but I have yet to find a copy of that report as published that Kuechler might have seen.
The Delaware Creek value of magnetic declination is particularly strange considering that the maximum East declination between 1850 and 1880 was only 11å¡38' East. So where did 13å¡55' East come from?
The value of 9å¡45' East at Fort Phantom Hill looks suspiciously like a value lifted from the records of the Texas GLO, but the actual section that Fort Phantom Hill occupies was apparently not surveyed until 1881. The patentee, C Von Carlowitz,, was himself a surveyor and probably had an inside track on the land.
From my early years of transit and compass use, local deviation from normal variation was always hard to explain and keep up with.
I believe it takes a solar compass to give a value to local magnetic variation.
A Harris, post: 382187, member: 81 wrote: I believe it takes a solar compass to give a value to local magnetic variation.
Most of the surveying textbooks of the day describe how to determine magnetic declination by polaris observation and an ordinary compass. That was what Jacob Kuechler did.
I keep forgetting that some surveyors burn the night away sighting the stars while others tabulated their solar settings waiting for supper.
:beer:
A Harris, post: 382215, member: 81 wrote: I keep forgetting that some surveyors burn the night away sighting the stars while others tabulated their solar settings waiting for supper.
Here's a pdf of the chapter from Gillespie's 3rd Edition published in 1856 that describes several different observations that were used to determine a true meridian from which compass observations would determine the variation or declination. Note the variety of techniques that were described and the simpicity of the observations.
Kent McMillan, post: 382174, member: 3 wrote: The value of 9å¡45' East at Fort Phantom Hill looks suspiciously like a value lifted from the records of the Texas GLO, but the actual section that Fort Phantom Hill occupies was apparently not surveyed until 1881. The patentee, C Von Carlowitz,, was himself a surveyor and probably had an inside track on the land.
I had an idea on this, having done a survey just west of there, where Elm Creek and the Clear Fork come together, but I am not at the office, the GLO map won't open on my home computer, so I guess it will have to wait. I also have the thought that many surveyors started their lines from Ft Phantom Hill, and took off across the frontier to stake out the RailRoad surveys, and School Land Surveys, some many years earlier, so maybe thats were he got his information from.
A variation of 9å¡45' was nearly uniformly in use in Bexar Land District from the 1840s through the late 1870s. The surveyors in the land district that Jones County and Fort Phantom Hill was situated in may have followed the same practice.
Kent McMillan, post: 382216, member: 3 wrote: Here's a pdf of the chapter from Gillespie's 3rd Edition published in 1856 that describes several different observations that were used to determine a true meridian from which compass observations would determine the variation or declination. Note the variety of techniques that were described and the simpicity of the observations.
Project a stick out of the high window of a house, suspend a plumb line from it, then set up your compass [near the house which probably has iron nails in it]...
I'm drawing a blank right now, but I am thinking that this area might of been Bexar Land District before the counties were formed. I been stuck in the panhandle too long.
It would be interesting to experiment with different techniques for determining a true meridian as efficiently as possible using only the most basic tools such as a compass sight, a plumb line, et cet. to set up the meridian. A plumb bob string at 10 ft. should subtend an angle of only about a minute of arc, so should be perfectly fine as an aid to sighting polaris as long as one was well away from city lights and the night sky was as clear as it gets in West Texas.
Monte, post: 382226, member: 11913 wrote: I'm drawing a blank right now, but I am thinking that this area might of been Bexar Land District before the counties were formed. I been stuck in the panhandle too long.
Per the Handbook of Texas:
"Jones County was established on February 1, 1858, from Bexar and Bosque counties."
So part of Jones County was situated in Bexar Land District and part in Milam Land District. Jones apparently wasn't organized (and didn't elect a county surveyor) until much later and would have remained attached to some other land district. So, it's possible that the variation of 9å¡45'E used throughout Bexar District in the 1850s and 60s remained in use in Jones County into the 1870s.
Kent McMillan, post: 382227, member: 3 wrote: It would be interesting to experiment with different techniques for determining a true meridian using as efficiently as possible using only the most basic tools such as a compass sight, a plumb line, et cet. setting up a meridian. A plumb bob string at 10 ft. should subtend an angle of only about a minute of arc, so should be perfectly fine as an aid to sighting polaris as long as one was well away from city lights and the night sky was as clear as it gets in West Texas.
Indeed it would. I have been wanting to take the old compass set up we have at the office to the High Plains Experience class that Maxey teaches at each year, and set it up after formal instruction was done, and show the class participants the old compass, how it works, etc, but you have made an awesome suggestion. I could set it up, and out there in the panhandle, where it is dark save for 1 guard light, should be able to sight in polaris. If I may use your idea, I'll work on adding that to the mix for next year.
My 4" K+E staff compass will be 1/2 degree off if my car is parked 50' away but it's right on in my backyard under the power lines. I obtained two lines with geodetic bearing by use of Polaris observations and the LaPlace correction.
My iPad and this website don't get along very well.
There is so much history that went on in this stretch of Texas I am not able to keep up with it all. I read the diaries I can, and the articles, books, etc. But the frontier line of forts ran through here from around 1840's until 1870's as the west expanded out. I was fortunate enough to do a boundary reconstruction this last spring, where the calls were to stones set in the curves of the old Ft Griffin to Anson road. It was where the road crossed the Clear Fork of the Brazos. Upon searching, I was not able to find the stones, but did find evidence of the old roads, and it occurred to me, that was the road that many famous men traveled headed to the west. It was the only good crossing of the Clear Fork going west from Ft Griffin for quite a ways. I was riding my horse down the same road that men like Pat Garret, Wyatt Earp, Bat Masterson, and who knew who else had gone down. I really enjoy surveying in Texas.
Dave Karoly, post: 382231, member: 94 wrote: My 4" K+E staff compass will be 1/2 degree off if my car is parked 50' away but it's right on in my backyard under the power lines. I obtained two lines with geodetic bearing by use of Polaris observations and the LaPlace correction.
I found my cell phone case magnet closure to affect my compass, but not after a few minutes of head scratching. I felt a bit silly for not realizing it sooner.
Monte, post: 382230, member: 11913 wrote: Indeed it would. I have been wanting to take the old compass set up we have at the office to the High Plains Experience class that Maxey teaches at each year, and set it up after formal instruction was done, and show the class participants the old compass, how it works, etc, but you have made an awesome suggestion. I could set it up, and out there in the panhandle, where it is dark save for 1 guard light, should be able to sight in polaris. If I may use your idea, I'll work on adding that to the mix for next year.
I'm going to guess that observing Polaris through the compass sight vanes would be quite a trick, but using plumb lines to set up the meridian first and extending it to set a more distant point that the compass can sight from a set up would work pretty well. You'd need a dim lantern to illuminate the forward string when sighting Polaris, I'd also bet.
The main bit of pre-planning would be to calculate the elongation times to see if upper or lower culmination or elongation will be the most feasible observation for the demo. If elongation, the azimuth of polaris at elongation at intervals of latitude can be provided as a sort of field table of the sort that 19th-century surveyors would have had. From the field table, an azimuth at the latitude of observation can be interpolated based upon a latitude determined by some method. It would be a fun exercise.
The plate and screws in my right wrist definitely affect a compass too.
Andy
I'm thinking that those places may be points along the Butterfield Overland Mail route , which Kuechler's survey followed in places, camping at some of the abandoned stage stops.
https://butterfieldoverlandstage.com/2012/03/28/texas-stations/
On Google Earth, a N32 43 34.41 W99 37 36.41 you can find the Alexander Ranch house, and at N 32 43 51.27 W 99 37 46.12 the old Ft Griffin to Anson road crossing. The crossing is as confirmed as it can be by the earliest available USGS Topos, and stories by locals. If thats the case, it changes the butterfield map by a couple of miles, with the chance the route for the butterfield having been changed some during the years. am familiar with the ruins of a Butterfield station at Valley Creek, shown on the map.
