Here's another interesting feature of the 1882-vintage survey I'm retracing. The 1882 surveyor located at least five contiguous land grants as a more or less continuous surveying operation over the span of two days. His field notes (metes and bounds descriptions for non-Texans) give various passing calls on topo features such as creeks and on a public road that was in place at the time. While the creeks are generally quite narrow, well defined channels a couple of varas wide and the traveled way of the road was probably not much more than 5 varas wide, the passing calls are nearly uniformly given to the nearest 10 varas.
Assuming that the 1882 surveyor was using a 10 vara chain (as seems most likely), and without knowledge of actual conditions on the ground, what would the most probable value of a passing distance measured to a creek and reported as 550 varas be?
I think that the answer comes from 19th-century chaining procedures whereby the count of chains was kept by tallying chaining pins and the follower or tail chainman having a count of the number of whole chains that had been run out at any time in the form of the number of pins he had collected and the number or outs or multiples of ten that had preceded the event. So, when the line crossed a creek, the surveyor could ask the tail chainman how many pins he was holding and, together with the number of "outs" that had been noted, that would give a passing distance on the creek that would at least be in the ball park. So, if that method was used (as seems likely), what was the most probable actual passing distance for one reported as 550 varas?
545+/- Varas
If I am reading you correctly, somewhere within that last 540-550 chain they passed the call.
What does your retracement field evidence say?
Paul in PA
The crew would have been out at 556v. If the lines were run on the ground it doesn't seem like a plus or minus situation, they would have easily noticed the creek as a back station.
So somewhere between 1543' and 1515'
5+50 < 5+60
> If I am reading you correctly, somewhere within that last 540-550 chain they passed the call.
I think that it's more likely that the passing calls were based upon outs and pins held at the time, the passing calls to the nearest 10 varas being consistent with use of a 10 vara chain. So a creek reported as passed at 5+50 varas would have been somewhere in the 10 varas AFTER 5+50.
Rear Chainman Holds The Pins
So when the rear chainman is at 550 the head chainman is at 560, i.e. 555+/-.
Again I ask what does the resurvey field data imply?
Paul in PA
Rear Chainman Holds The Pins
> Again I ask what does the resurvey field data imply?
The one passing call that I've checked so far is on a creek with a 2 vara wide bottom in solid limestone. In other words its in the same spot it would have been in 1882.
The 1882 surveyor called to pass that creek at 550 varas and the distance is actually 552.5 varas. The line drops 172 ft. (= 62 varas) over that distance.
> The crew would have been out at 556v. If the lines were run on the ground it doesn't seem like a plus or minus situation, they would have easily noticed the creek as a back station.
I'm afraid I don't understand what you've posted. An "out" for chaining with a 10-vara chain means ten chains. That's the point at which the last pin carried by the head chainman is in the ground and the rear chainman walks forward and gives him the ten he has picked up over the last 100 varas.
The fact that virtually all of the passing calls are the nearest ten varas indicates that they didn't break chainage at the feature, but chained past it and noted the distance by some means that probably was based upon the count of chains. So the choices would be the number of chains before the creek was actually crossed, represented by the number of outs tallied and pins held by the rear chain carrier at the time or adding 10 varas to the distance that would be calculated from outs and pins. The former is the simpler and no less accurate than the latter, so the former is the logical choice.
That's my mistake in back and forth calculations between feet and varas. I have no idea how I did that.
Out would have been 1389' and 1667'. 550v +/- with a ten vara chain is somewhere between 1514' and 1542' and I guess that all depends on where you cross that creek relative to the angle of intercept.
Sorry about the 556v I have no idea where my head went on that.
What's a few varas among friends?!
> What's a few varas among friends?!
What's interesting is that one also sees passing calls to the nearest 100 varas in other 19th century surveyors's work. If they were following the same method as the 1882 surveyor, i.e. reporting the last even 10 varas chain distance as the passing distance, that would alter the 100 vara distance by an average of 50 varas.
Part of retracement work is figuring some of these practices out that were widely followed and underdocumented.
I've reviewed a lot of GLO notes where the calls are either even chain or half chain. They where chained with a 2 rod (half length) chain. I often wish they'd been a little more specific.
Wouldn't ten varas be in about the same range as a half chain?
I think your theory assumes facts not in evidence, like that the chainmen could actually count. The level of education for a laborer up until the 1940's didn't necessarily imply that reading and writing were requisite.
Counting pins may have been a problem for the "low man on the totem chain".
> I think your theory assumes facts not in evidence, like that the chainmen could actually count.
Okay, if this were in East Texas, you might have a point (but probably not). Everywhere else in Texas being able to count to ten was not considered the product of higher education. Counting was an even more fundamental skill than literacy.
> I've reviewed a lot of GLO notes where the calls are either even chain or half chain. They where chained with a 2 rod (half length) chain.
Well, the same situation might just apply, i.e. that the chainage was based upon the number of pins that the rear chainman was holding when the feature was passed, not that the actual distance was measured and then rounded up or down to the nearest even chain or half chain.
Calls like this help in the search but sort of cause heartburn if you want to reset a corner from them.
> Calls like this help in the search but sort of cause heartburn if you want to reset a corner from them.
The first thing is to actually plot the calls on topography, but if the calls are to the nearest 100 varas, then they will probably be actually longer by an average of 50 varas even if the chaining is free of systematic errors.
Knowing how to interpret passing calls with rounded distances is just another way to narrow the search area. While passing calls tend to be regarded as notoriously inaccurate, it may well be that the problem is merely one of properly reckoning their uncertainties and systematic errors.
I think I'm following this right.
If they chained past the creek and the chainman called out 550 and the surveyor was at 560 but the creek was 'obviously' (to them) closer to the chainman (I assume he is in the rear and surveyor out front) then would it be fair to assume they'd say it was at 550, but if nearer to the surveyor then call it at 560?
I would have thought they could split it and say 555 but sounds like they just used whole parts.
That would still give you a rather wide window of variation which is not too helpful.
That's how I would do it if I was measuring that way and trying to be a bit more accurate without wanting to be too accurate! That's the part that bothers me! Why be so 'loose' in something I assume had some value.
Or did they just think it was an aid to finding your way about rather than future surveyors retracing their work and using those measured distances to remark lost corners?
> If they chained past the creek and the chainman called out 550 and the surveyor was at 560 but the creek was 'obviously' (to them) closer to the chainman (I assume he is in the rear and surveyor out front) then would it be fair to assume they'd say it was at 550, but if nearer to the surveyor then call it at 560?
I think for that level of effort, they could have as easily paced the fractional distance from the last 10-vara station or, better yet, have read the actual chainage. So, since the distances were rounded to the nearest 10 varas, it makes best sense that it was operationally simple to do so (and a passing call on a creek that was in error by even 10 varas was hardly the end of the world). So, if simplicity was the goal what is simpler, to just have the rear chain carrier call out the chainage when the line passes a feature, based upon the number of pins he was holding with the surveyor keeping track of the "outs" or multiples of 100 varas run out on the line so far, or any other scheme? For my money, reporting the last even 10-vara station before passing the feature was operationally easiest, something that just about any chain carriers could manage since all they had to do was report tallies of 10 x 10 varas and number of chaining pins held at any particular station.
> I would have thought they could split it and say 555 but sounds like they just used whole parts.
It's also useful to recall why the passing calls were mentioned in the field notes. They served two main purposes: (a) to assist in plotting up the bits and pieces on an overall map in relation to waterways (most of the original Texas surveys were identified by the drainage basin of the waterway in which they fell) and (b) to give a good clue that would put one in the general locality of a corner by chaining back along a marked line that crossed a waterway for the distance mentioned. It was assumed that the creek itself would be insufficiently distinct as a feature to have any real locative significance closer than about 10 varas. My example of the 2 vara wide creek is ununusual in that respect.
> That would still give you a rather wide window of variation which is not too helpful.
> That's how I would do it if I was measuring that way and trying to be a bit more accurate without wanting to be too accurate! That's the part that bothers me! Why be so 'loose' in something I assume had some value.
> Or did they just think it was an aid to finding your way about rather than future surveyors retracing their work and using those measured distances to remark lost corners?
Yes, I think it was assumed that the purpose of the passing calls was to identify the general vicinity of the corner where, once there, the actual corner itself could be identified from its marks or from the marked lines leading to it.
