I've just spent a few days sorting out some lost railway cadastral boundaries here in Tasmania.
They ripped the line up about 40 years ago and the land has been farmed since then.
Some old well defined cuttings and embankments exist but little else.
The railway centreline was surveyed in 1912 and the boundary is 1/2 a chain each side of that.
Here in Tasmania its hilly, and straights are seldom longer that 150 meters and curve follows curve follows curve.
Just curious if you have old rail surveys (I imagine you would) and how accurately you have found the rails were placed in relation to the intended design.
I referring to old lines not modern fast networks.
I came to the conclusion on my work (3 km of line) here they didn't follow the original centreline too well, deviating in places up to 1 metre.
I was told by an engineer with a strong interest in railroad history that would be typical of how the rail was built.
An old railhand also intimated that could be expected.
> I've just spent a few days sorting out some lost railway cadastral boundaries here in Tasmania.
> They ripped the line up about 40 years ago and the land has been farmed since then.
> Some old well defined cuttings and embankments exist but little else.
>
> The railway centreline was surveyed in 1912 and the boundary is 1/2 a chain each side of that.
>
> Here in Tasmania its hilly, and straights are seldom longer that 150 meters and curve follows curve follows curve.
>
> Just curious if you have old rail surveys (I imagine you would) and how accurately you have found the rails were placed in relation to the intended design.
> I referring to old lines not modern fast networks.
>
> I came to the conclusion on my work (3 km of line) here they didn't follow the original centreline too well, deviating in places up to 1 metre.
> I was told by an engineer with a strong interest in railroad history that would be typical of how the rail was built.
> An old railhand also intimated that could be expected.
Well, if they built rail the same way the U.S. did 10 years ago, then the engineers tended to calculate curves by even degrees of curve, and calculate angles and distances to the stationing along the curve by occupying the PC and backsighting the PI.
Is there any way you can factor in the original builders methodology and come to a conclusion about the layout of the track?
Richard:
We have a pretty poor time trying to reproduce main line RR layouts around here. The tracks have been re ballasted so many times the monuments are lost, sometimes we are lucky and find RR Rail bounds placed along the sidelines, but that is seldom. The older unused sidlines usually still have the stone center line moniments in place.
I ran about a mile and a half along a major RR line locating the rails as I went, after some calculations I found that the rails move around and were 4' to 6' out of the center at times. We do use the rails at times to define the R/W if there is no other evidence to be had, but it is poor practice. Many of our older lines have been coverted to "Rail Trails", which are bike paths, paving over any remaning monuments in the process, a sad situation.
The RR's around here use chord definition for stationing, measuring along 100' chords rather than along the actual arc.
Good luck with your project.
T.W.
Richard: I always look for the following evidence on an abandoned railroad:
Bridges, Bridge abutments, Culverts, Mile markers (concrete posts).
Rail left in the roadways at crossings (it was often easier to cut the rails at the crossings than tear up and have to rebuild the road crossing)
I'm still trying to get my head around chains and meters in the same statement! How long is your chain?
I should have been more clear - when I referred to stationing layout I was trying to convey that they would have used the chord method.
Actually a 10 meter chain ...
is so close to a 1/2 chain (2 poles) that they are essentially interchangeable once they have been used, bent, stretched, broken & repaired.
32.808333' vs 33'
Actually a 10 meter chain ...
I was wondering if they did measure in rods/poles and chains down there. As if US surveyors started the surveys..
Is a 20 meter chain a standard of measurement in Tasmania?
Actually a 10 meter chain ...
Don
Australian dimensions have the same history as the U.S.. English Chains & Acres converted to feet until the 1960s when the country convert to metric.
Actually a 10 meter chain ...
I do have several 10 meter chains in my collection and I am convinced that they have been used interchangably over the years. This is based on the frequency and locations that they appear.
I have never seen a 20 meter chain, but that's not to say they don't exist.
Rail Roads vs. Rail Ways
It's a Rail Road if originally financed by a U.S. Bank.
It's a Rail Way if originally financed by a British Bank.
True in the U.S., anyway.
@ Foggyidea
its confusing to say the least.
We move away from feet and chains/ links ages ago and now purely metric, but obviously still work with old surveys.
The rail surveys are along the centreline and show IP's (intersections of tangents), TP's and radius and arc lengths of curves.
They also show ties from the centreline to side boundaries they cross, as well as the arc to tangent measurements along the side (property) boundaries.
Now it gets confiusing.
All old cadastral surveys were in links and chains. 100 links = 1 chain = 20.1168 metres.
But the rail surveys were in links, chains and also miles.
So running chainages are for example 1M (mile) 45C (chains) 10.5L (Links)
It made me think as its a long time since I worked on such.
Once one gets past the next 80 chains (= 1 mile) then the incrementing Mile chainage is shown.
Yes I concur with Marc Anderson on the evidence and order of that.
Unfortunately in these cases they didn't leave any permanent marks which is pathetic.
Your (US) way of monumenting is something I give your sytstem a big plus for.
We relied on marking trees and stonepiles but given land clearing in rural areas since the 1850's to 1900's when most development (granting of land) took place thats extremely rare to find anything these days unless its undeveloped and unfenced land.
Its an intersting side to surveying and has been (is) probably one of my most challenging jobs to date due to the absence of any real evidence.
I made an initial assumption the centre of the narrow track where it existed would be the 'best evidence' but it has not proved to be.
Thanks for input.
