>Just finished reading "Conquering Gotham - Building Penn Station and Its
>Tunnels"
>An excellent read on both construction practices and the incredible
>corruption that infiltrated New York politics during the early 1900's.
Agreed.
>In the book the author states that engineers began digging the tunnels on
>opposite shores to eventually meet in the middle.
>And they used a 30 foot tower on one shore as a fixed alignment point.
>So exactly how does one use an above ground alignment tower while deep in
>the muck under a river?
How about a periscope?
In general, surveying has been around a LONG time.
A tunnel is less of a challenge than mapping India,
for example.
--
A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433
it is impressive what people were able to pull off years ago without stuff
like like computers and gps.
Probably used to locate where they sunk the caissons:
http://www.americanheritage.com/places/articles/web/20071113-holland-tunnel-transportation-new-york-new-jersey-hudson-river-civil-engineering.shtml
A few years back, when I was contracting for AT&T, I rescued from a
Verizon dumpster an engineering notebook with all sorts of
correspondence about building the trans-Atlantic telephone cable. I
remember thinking that it's a miracle that they got this done without
the internet, and then I realized that they did it without even a
telephone - which they were working to connect.
The 1955 cable?
My father worked for Simplex Wire and Cable in Newington NH, which
made the cable and loaded it onto the ship. I still remember the huge
machine that spirally wrapped each layer onto the core, Afterwards he
brought home a souvenir short piece of it in Plexiglas.
Their quality control was very strict and much of the material was
rejected, and then appeared as scrap all over the area. I had a roll
of the heavily galvanized armor wire and some copper foil, which I
used to cover the bottoms of my model sailing ships.
jsw
They use standard surveying techniques:
http://en.wikipedia.org/wiki/Surveying
http://en.wikipedia.org/wiki/Triangulation
By building a tower or two, they create fixed reference points that can
be seen from both sides of the river. The location inside each tunnel
section can then be determined relative to each of these points.
--
Paul Hovnanian mailto:Pa...@Hovnanian.com
------------------------------------------------------------------
"Nothing Important Happened Today"
-- King George III, diary entry July 4, 1776
http://en.wikipedia.org/wiki/Great_Trigonometric_Survey
http://en.wikipedia.org/wiki/Metre
jsw
>A few years back, when I was contracting for AT&T, I rescued from a
>Verizon dumpster an engineering notebook with all sorts of
>correspondence about building the trans-Atlantic telephone cable. I
>remember thinking that it's a miracle that they got this done without
>the internet, and then I realized that they did it without even a
>telephone - which they were working to connect.
Unless you are sure your heirs will treasure it, please will it to the Smithsonian.
Wes
_Elementary_Surveying_. An accurate transfer of direction and level into
the hole, checked several ways - no periscopes involved. If you handle
"dry" material well, check out a copy of Breed and Hosmer. Mine (8th
ed.) dates from the 1950's, the content may not have changed since 1931.
Underground Surveying is covered in articles 355-380. There is also an
extensive list of references for more detail at the end of article 380.
If you'd like a challenging hole to consider, consider the spiral
railway tunnels west of Lake Louise in Canukistan, which were also dug
from both ends to the middle.
Accuracy is not a 20th century invention, though it has been refined and
made easier to come by.
--
Cats, coffee, chocolate...vices to live by
No, a periscope at shore. Build such so it is a perfect U;
in other words, light shined in one end comes back
in the plane/parallel to the source. Turn it on its side;
with one end at the dig depth, and the other looking at
the tower on the other shore. The two mirrors are in sync.
-------< <-laser in
|
|
|
|
| ______ ground level_________
|
|
|
-------< laser out--> |more dirt here
Shine a laser in from the far side; it enters the
periscope, does a 180, and shines on the face of the dig.
That's where you start drilling/blasting/etc.
Now, they din't have lasers, and a 100 ft tube would be
a PITA, but I'm sure surveyers have a way I don't know
about of syncing the two 90 degree angles.
Well, that's a lot of help <G>. If I didn't want to buy a copy (and
there's no way our library has it), could you give a very brief summary
of a common technique?
If I had to do it, without knowing any surveying & without buying a
book, I'd drop a plumb line from 2 points at the top, to get a line at
the bottom that had the same bearing.
Bob
> Ecnerwal wrote:
> > _Elementary_Surveying_. An accurate transfer of direction and level into
> > the hole, checked several ways - no periscopes involved. If you handle
> > "dry" material well, check out a copy of Breed and Hosmer. Mine (8th
> > ed.) dates from the 1950's, the content may not have changed since 1931.
> >
> > Underground Surveying is covered in articles 355-380. There is also an
> > extensive list of references for more detail at the end of article 380.
> ...
>
> Well, that's a lot of help <G>. If I didn't want to buy a copy (and
> there's no way our library has it), could you give a very brief summary
> of a common technique?
You might actually check your library - it's the standard reference in the field.
> If I had to do it, without knowing any surveying & without buying a
> book, I'd drop a plumb line from 2 points at the top, to get a line at
> the bottom that had the same bearing.
That's one method. If you have two places further apart (ie, two shafts in the the tunnel) you can get more separation and reduce errors. If the tunnel comes out to the surface you can transfer a line from surface references into the tunnel directly. If it does not, there are (or were) special mining transits set up to deal with the problems of odd angles.
Try this (or go look for the title on google books):
http://books.google.com/books?id=qOZIAAAAIAAJ&pg=PR1&dq=elementary+surveying+breed+hosmer&cd=3#v=onepage&q=&f=false
Page 332 or 334. 321 for the start of the section. 360 for tunnels
Bonus points for the Google Books reference. Interesting stuff.
>
> Well, that's a lot of help <G>. If I didn't want to buy a copy (and
> there's no way our library has it), could you give a very brief summary
> of a common technique?
...has a section on underground surveying.
Kevin Gallimore
Oh, you're right ... kind of. Our library itself doesn't have it, but
the consortium of 20 or so towns that it's in, does. Not that I'm that
interested in reading it <G>.
Bob
This looks like a good time to mention the Tamarack Mines
mystery once again. Check out this link:
http://www.lhup.edu/~dsimanek/hollow/tamarack.htm
Here is an excerpt (sp? ;>)) ) from the article:
From the new No. 6 shaft, the deepest perpendicular shaft
in the world, it was desired to crosscut a distance of 800
feet at the twenty-ninth level, or 4,250 feet from the
surface, over to the lode. Already from the twenty-ninth
level of No. 2 shaft, which is 3,220 feet at the surface
from No. 5... the engineers desired to solve the old
tunneling problem�that of beginning work at either end and
meeting somewhere near the centre.
In order to do this it was necessary to give the men
working from the No. 2 shaft drift the proper direction.
Already they had at the mine office a survey from which it
would have been possible to have begun work, but it was
desired to verify it. It was made years ago, and the
engineers thought that the opportunity of satisfying
themselves as to its accuracy was at hand. The dropping of
the plumb line was the first step.
Chief Engineer J. B. Watson and his assistants went to
work to use the method that had been tried many times. It
had been tried at the Tamarack mine before and had been a
complete success. At the vertical shaft of the Calumet &
Hecla, known as the Whiting or Red Jacket shaft, plumb lines
had been dropped by the engineers, and at other mines where
vertical shafts are in use it had been successfully tried.
In principle it was nothing new, but it was practically new,
as never before had it been necessary to deal with a shaft
close to 5,000 feet deep.
The idea was to drop two plumb lines down the shaft to the
twenty- ninth level, then to take observations both at the
surface and down in the mine, taking the same data. After
this had been done at the new shaft it would be necessary to
repeat the operations again at the old shaft, when it would
be possible for the engineers to give the miners, working
away from the old shaft and toward the new one, the proper
directions to enable them to meet the men working in the
opposite direction. The idea was a simple one and one that
is known to all mining men.
>Accuracy is not a 20th century invention, though it has been
>refined and made easier to come by.
Consider the dead straight 328 mile section of the
Trans-Australia Railway.
[...]
>
> _Elementary_Surveying_. An accurate transfer of direction and level into
> the hole, checked several ways - no periscopes involved. If you handle
> "dry" material well, check out a copy of Breed and Hosmer. Mine (8th
> ed.) dates from the 1950's, the content may not have changed since 1931.
[...]
> Accuracy is not a 20th century invention, though it has been refined and
> made easier to come by.
You can go back to Greece in the 6th century B.C. to see a similar, if
land-based, problem and its solution:
http://en.wikipedia.org/wiki/Tunnel_of_Eupalinos
I _thought_ I had seen a television show describing this on PBS, The
History Channel, or one of the Discovery channels but I was unable to
locate it.
Enjoy...
Frank McKenney
--
...[B]ecause his martyrdom is thus a power to the martyr, modern
people think that any one who makes himself slightly uncomfortable
in public will immediately be uproariously popular. ... The
assumption is that if you show your sincerity (or even your
political ambition) by being a nuisance to yourself as well as to
other people, you will have the strength of the great saints who
passed through the fire.
-- G.K. Chesterton: The Modern Martyr (1908)
--
Frank McKenney, McKenney Associates
Richmond, Virginia / (804) 320-4887
Munged E-mail: frank uscore mckenney ayut mined spring dawt cahm (y'all)
> A few years back, when I was contracting for AT&T, I rescued from aVerizondumpster an engineering notebook with all sorts of
> correspondence about building the trans-Atlantic telephonecable. I
> remember thinking that it's a miracle that they got this done without
> the internet, and then I realized that they did it without even a
> telephone - which they were working to connect.
OK, I got the book out of storage, and took a picture of a more-or-
less randomly selected page. If anyone wants to see more, I'll see
what I can do about (maybe) scanning the whole thing.
http://i1029.photobucket.com/albums/y358/RangersSuck11/SamplePage.jpg
Note that all of this was dated 1929.
http://i1029.photobucket.com/albums/y358/RangersSuck11/SamplePage.jpg
**********
An engineering notebook with typewritten page(s) on unyellowed paper
from 80 years ago?
I'm skeptical.
Art
"Artemus" <bo...@invalid.org> wrote in message
news:hqd665$erk$1...@news.eternal-september.org...
1. typewriters existed in 1929, I have a collection of them going much
farther back than that
2. paper yellows if it has high acid, and is exposed to light - I have books
from 1800 where the pages are not yellowed at all, and I have a manuscript
from about 1150 which also shows no yellowing
so, you can be skeptical, but it looks consistent to me.
I bet that the Smithsonian would be very interested in this book.
The IEEE may also be interested.
Joe Gwinn
>An engineering notebook with typewritten page(s) on unyellowed paper
>from 80 years ago?
>I'm skeptical.
>Art
I don't agree with rangersucks on much. This, I doubt, is a fabrication.
Wes
Sheesh, give me a break, huh?
It's not exactly an engineering notebook. It's a book of bound
(punched holes) mostly typewritten, some handwritten, correspondence.
Some is logistical, most is engineering (like the page I posted). The
picture you saw is not yellow because I posted it in grayscale. OK?
Most of the pages are in remarkably good shape. Some are carbon
copies, though many are original. There are also a few blueprints
bound in.
Why would I ever make something like this up? The book was in a
dumpster at a Verizon office where I was working under contract to
AT&T about 10 years ago. Can you believe they were throwing something
like this away? I got a nice Cisco router out of the same dumpster.
The Verizon guy was happy to see it go.
It is, indeed, the real deal. Or, someone went to a great deal of
trouble to put together an old-looking book and toss it in the junk
pile. All just to fool the guys on rcm.
>
> Why would I ever make something like this up? The book was in a
> dumpster at a Verizon office where I was working under contract to
> AT&T about 10 years ago. Can you believe they were throwing something
> like this away?
That was how Kevin Mitnick got the goods on AT&T's hardware and software.
They just throw operations stuff in the trash. Well, they used to.
LOL
--
John R. Carroll
I have some of my Dads from the 30's and 40's and 60's.
They are good. The real issue is a patent level book should be of high
quality paper since it is first proof...
Martin
Martin
Artemus wrote:
> "Bill Noble" <nob...@nowhere.invalid> wrote in message
> news:hqd740$ho3$1...@news.eternal-september.org...
> My skepticism is regarding whether the OP has an engineering notebook.
> Not whether the contents are authentic or not.
> 1. Engineering notebooks typically have bound pages which are sequentially
> numbered. This is more for legal requirements (ie patents) than for any engineering
> need. Getting these pages into a typewriter would be extremely difficult and
> highly unlikely IMO.
> 2. Engineering notebooks aren't (and probably weren't in 1929) made of
> archival quality (low acid) paper. I have seen old notebooks from the '70's
> that haven't seen the light of day for 30+ years and even they are slightly
> yellowed.
> Art
>
>
http://en.wikipedia.org/wiki/Port_Authority_Trans-Hudson
http://en.wikipedia.org/wiki/File:PATH_junction.jpg
That looks like the surveyors would have had enough distance to get
the beginning of the tunnels tunnels lined up before the stuff on land
got covered. More distance between survey points means more accuracy
but I'm sure there's a calculation to figure out how far apart the
first two points needed to be to give them the precision to meet up
with an acceptable error in the middle of the river.
Karl
*****************
Thanks for confirming my skepticism about it being an engineering notebook.
Art