STADIA

[Berk Blake, PLS CA]

Hello Robert:

I have a set of field notes by a Louis Ross who states that he was using stadia in the survey I was retracing due to the rugged terrain, circa 1910

[Berk Blake, PLS CA]

3% to 15%, rugged terrain

[LA Stevens]

What are the approximate distances being measured? If it is a steep slope and the rod was not plumb, I can see some large errors occuring. It was a must to have a rod bubble for steep terrain when I started. Any one know when the rod bubble was invented?

[Berk Blake, PLS CA]

The work reads just like all the other government field notes that I have read. Chainage to streams, ridges, etc. and nothing as to lengths with the stadia rod.

[Dave Karoly, PLS]

We have copies of some Hermann field notes in the files where he resurveyed a Township in the 1880s. This was rough terrain in the coastal mountains. He set up on high points and did radial survey using stadia for distances.

I also retraced Tivy in 1855 in extremely steep desert terrain where he was hitting as close as 7' in the half mile. I doubt very much he chained that on line; I can't even walk some of it. But I don't have any direct proof he did measurements from high point to high point with stadia but he certainly could have easily done so. There isn't a tree within a hundred miles.

Back to Hermann: if you read the GLO Field Notes they look like any other set of GLO Field Notes.

The GLO Field Notes were not done in the field; they were done later in the office. I think of them as being the same as a narrative Record of Survey. Everyone knows you don't draft the R/S out in the field as you go; it's done later after the field work is done. It's the same with the GLO Field Notes.

[btaylor]

Dave, among your records, do you have any surveys done along the Rancho Canada de Raymundo line along the coastal mountains where present day Skyline Blvd. is, southerly of Highway 92? I know there is a small State Park in the area southerly of where I am working. Specifically if there are references to rancho stations 49-52.

This is my current fixation. The wife has been told this takes the place of me purchasing a Ford Mustang Bullitt or a jet boat.

[Greg Ippolito]

Santa Clara DPW has many of the Hermann Brothers files and field notes. They cover areas outside of Santa Clara County. It might be worth checking there.

[goodgps]

It has been rumored to me, that . . .in the mountainous areas of the west side of the San Joaquin Valley, stadia was used to "shoot" from hill top to hill top to avoid riddulously steep terrain. This explains the absolute lack of obvious "topo" calls on the field notes. or if the calls were listed, they were in gross error (as if eye-balled)

This may have taken place circa 1878ish. Armed withthis idea, we have had good success by simply going near an area for a corner, and using only those close proximity topo calls. Topo calls for arrival and departure from a corner location seem to be (accurate as if measured).
Another key piece of evidence that stadia may have been used in such harsh terrain, is the uncanny total distance accuracy of the total "mile" or "half mile"

In the mountains of the gold country, where surveyors like Beavous and other famous names trod, the method was definately chained and topos calls are dutifly noted. YET, the total mile accuracy is a standard +/- 250 feet.
in similar terrain.

NOW, on the contrary, it must be understood that many of the old GLO notes and records were destroyed in 1906 during the San Francisco earthquake.
The notes we try to use today in those west hills, may simply be transcripts scaled from the GLO plat. I dont know these facts to be 100% , however, measured evidence has some merit.

It is very important to understand the history of "how it was", in order to better understand "how it is"

:*) Happy Holidays "good"

[btaylor]

Greg, thanks, I was thinking of doing that. Is there an index that makes things somewhat easy? I am not familiar with researching there.

[Greg Ippolito]

I’ve only been there a couple of times myself. The staff was very helpful and helped me with my research. They have a couple of ways of searching through the files. They even have an old client book, which lists many of their clients and a brief description of what was surveyed and where. So if you happen to have a name of someone during that time frame it could help.

[btaylor]

Thanks, I figured it was like that. It can be tough to research that kind of stuff if you are not in a subdivision that you can easily reference. You need to go in knowing a lot of old owner names at the time, or else you can easily miss some important records.

[Dave Karoly, PLS]

what the Santa Clara Surveyor has is amazing. The actual pencil drawn originals from the 19th Century.

Old Field Books, etc.

[Dave Karoly, PLS]

you mean Burleigh Murray Ranch State Park?

let me know the particulars via e-mail and I'll look into it Monday.

dkaroly@parks.ca.gov

[btaylor]

Dave

No, looking at the Thomas Giude, what I thought was a small park is the northeastern finger of the very large "Purisima Creek Redwoods Open Space" coming off Skyline. I would not be interested in the boundary of that area - but it is off Skyline and very near the rancho line, and if one of your records from Herrman had this area, I would be interested.

But it sounds like I should just go down to Santa Clara County instead.

[hellsangle]

As told to me from an employee of an old surveying company in Marin County (1949-1980s):

old surveys (1950s era) . . . No-name had an instrument that was knocked over. Somehow, he calculated how far “offâ€￾ the vertical was in error. This error was corrected in the office, therefore, following the raw written notes . . . the calculations will appear wrong.

When no-name and no-name ‘crewed’ together in field during a boundary survey, No-name was on the instrument and No-name was pounding wood stakes. No-name would beat the hell out of the hub (i.e. cracked & split) because he hoped they’d deteriorate more quickly.

For some reason ONE FOOT was added to all of No-name's stadia distance reductions. No-name said something unusual about their instrument required them to add a FOOT!

Hope all is well with you, Robert!

Phil

[Dave Karoly, PLS]

My understanding is on some of the old instruments "zero" stadia was out in front of the instrument. So you had to add a constant to the stadia distance to get the true distance from the center of the instrument.

My Dad grew up in Mill Valley. One of his first jobs was working for a CE and LS in Mill Valley. He remembered certain of the old-timers used slope distances in the hills and you had to take this into account when retracing in the Marin County hills. I have no idea if this is true or not; just what my Dad remembered.

[LA Stevens]

I only have heard of one CE in Marin County who used sloped distances in the county. One reason a professional should be come involved in the local CLSA chapter to be assured he becomes knowledgeable of local customs or specific customs of surveyors.

If I recall, different instruments had different constants for stadia adjustment. Depending upon the instrument the x hairs crossed at a certain distance beyond the axis of the scope. It was a real coup when the x hairs occured at the center of the instrument. Some had up to a foot of adjustment. Everyone should have an older survey text which has the stadia tables at the back of the text. Dont need the 41 program if you have the manual. Before the 41 I was excited when someone got a reduction program for Stadia.


Remember to record what instrument you are using in the field. It may help others in the future figure out a possible problem with your work.

Dave,

I have many surveyors notes from Mill Valley. Would love to talk further about your Dads knowledge.