But I Digress...
> I could imagine maybe a Deputy working on the township boundaries stashed a bunch of equipment
That reminds me of a situation I encountered when I was still an apprentice and working on my first USFS boundary in the Sierra. Access to one of the lines we were retracing was a half-mile or so off-trail hike down a steep ravine. The party chief was an "older guy" (45 or so at the time; I was 25) in decent but not great shape. The hike out every day was unpleasant enough for him that he decided to lighten the load, so after the first day we would stash all our gear (except the battery) wherever we finished up -- just left it all in the woods: Wild T1, EDM, tripod, prism pole and supplies.
I was kind of uneasy leaving the expensive stuff behind, though there really wasn't much danger of anyone coming upon it (no one would hike that line unless they had to), and weather wasn't an issue. Still, I don't believe I'd do it now.
But I Digress...
I never leave the total station or even prisms but sometimes I leave tripods and poles setup. That is usually when I start on a road and know I will be ending on a road in a day or two but I never leave equipment over a weekend. My boss told me I could hide the TS but I just can't do that.
> > I'm wondering whether they got caught in a snowstorm, left some equipment with the idea of picking it up later and didn't.
Had the GLO not burned their notes after transcribing them, you might know the answer.
I worked with a fellow that had done some retracement work in the barren hinterlands of Edwards Air Force base in California in the late 1960s/early 70s. Said they'd found a GLO transit on top of a small mesa. Old notes indicated the GLO crew had beau coup troubles with the local tribes and had to skedaddle or lose their scalps. He said the transit was in a well preserved state and the company owner had it gussied up and on display in the front office. I'd like to believe the story, but this guy was a real crackpot. Maybe some of our Bear Flag brethren have heard of this???
100 ft. chain
> I don't know whether that pattern of tagging was commonly followed, but I'll bet it was.
Yes, that was the standard pattern, although I have at least one chain that doesn't follow that pattern.
100 ft. chain
> Yes, that was the standard pattern, although I have at least one chain that doesn't follow that pattern.
Well, that casts errors of nearly exactly 20 ft. on lines with a 4 or a 6 as the tens digit in a new light if the survey was made in units of feet during the period before nearly universal use of tapes. That is, a distance reported as, say, 562 ft. that on the ground looks as if it should have been 542 ft. or vice-versa now has an obvious explanation.
“From the '73 Manual . . . I don't think it's changed in the '09.”
The 2009 Manual adds two sentences to the longer paragraph you quote near the end of your post. The first of them needs correction, I think. The second paragraph of 2-42 reads,
The chain unit, devised in the seventeenth century by Edmund Gunter, an English astronomer, is so designed that 10 square chains are equivalent to one acre. In the English colonial area of the United States the boundaries of land were usually measured in the chain unit, but lengths of lines were frequently expressed in poles. One pole is equal to 25 links, and 4 poles equal 1 chain. The field notes of some early rectangular surveys in the southern States show the distance in "perches," equivalent to poles. The term now commonly used for the same distance is the rod. There are some places where distances were recorded in 2 pole (perch) chains, where a full mile contains 160 perches. The retracement surveyor needs to be cautious when retracing such surveys, particularly in poportioning measurements.
I do feel cautious around 160-perch miles.
Cheers,
Henry
But I Digress...
> I never leave the total station or even prisms but sometimes I leave tripods and poles setup. That is usually when I start on a road and know I will be ending on a road in a day or two but I never leave equipment over a weekend. My boss told me I could hide the TS but I just can't do that.
Dave,
Maybe he just doesn't like your work? 😛
> I have one 2-pole chain that was quite obviously made after 1810.
Made before 1810? I would say no. Before 1910? Not even sure about that.
> Made before 1810? I would say no. Before 1910? Not even sure about that.
>
>
Those links look galvanized. I don't believe I've ever seen (in my limited experience) an American-made surveyor's chain with galvanized links. The galvanizing may be a reflection of the rainy localities where the chains made by Mssrs. Rabone and Chesterman were ending up once upon a time.
Not American made, I believer that is a Chesterman chain, msde in Sheffield, Eng. and I seen another one just like it as well as my own which is not galvanized. I think they were experimenting with different treatments at the time, which was post 1900.
- jlw
> I believer that is a Chesterman chain, msde in Sheffield, Eng.
Look at the second photo. It's a "Rabone Chesterman, Made in England." I looked up Rabone Chesterman and found the following:
Michael Rabone carried on a business as rule maker at 8 Snow Hill, Sheffield in c1780; the business was continued by John Rabone and his (John's) grandson, Eric Rabone. It worked under the name of John Rabone & Sons c. 1784-1953, becoming a public company in 1948. The Headquarters were in Birmingham.
James Chesterman had set up business with Mr Housfield in 1821 with a factory in Nursery Street. Known as James Chesterman and Co Ltd from c1832 the business specialised in making measuring tapes and instruments.
The businesses were amalgamated in 1963. In 1990 it was taken over by Stanley.
Thus, it would appear this particular 2-pole chain was made after 1963.