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Details for Benchmark: LX4113

N 41° 06.606 W 073° 48.624 (NAD 83)

Altitude: 711

Coordinates may not be exact. Altitude is VERTCON and location is ADJUSTED. (more info)

Location:
In WESTCHESTER county, NY View Original Datasheet
Designation:
BUTTERMILK
Marker Type:
drill hole
Setting:
in rock outcrop
Stability:

Reference Points

Must Read!

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Found with MDsurveyor.

I am a Land Surveyor from Maryland and visiting this station has been high on my “to-do” list for quite a while. I was visiting the area for a geocaching trip and made sure we would make a stop here during the trip. The weather was great and I should have followed the direction in the log by BenchmarkHunter to find the easiest route to BUTTERMILK. I used my GPSr to find it and it shows 4 feet once I got there. Not bad for a hand-held GPS device.

I thought the plaque was nearby and while 72whalers and I were looking for it, we met a local jogger that was very interested in the history of the mark. We went back to show it to him and help eventually found the plaque and told us were it was.

It was terrific weather and I could envision Ferdinand Hassler standing here making his observations. I really enjoyed taking in the history while here and too bad you can’t give favorite points to Benchmarks.

[Photos:]
photoGPSr at BUTTERMILK
photoMe and the mark
photoCloseup of BUTTERMILK
photoAt the plaque
photo821 Meters East per my GPSr

When we learned we would be headed to Boston this week, we made this a target priority. We love finding benchmarks and it was great to come get the granddaddy of them all. Enjoyed the nice walk up to the spot. What a great piece of history here. Hard to believe these don't get found more often than they do!

[Photos:]
photoButtermilk

Found in good condition as described. Counting the twenty, or so, marks that I have found that are in the NGS database but not on this website, this was benchmark #1000 for me.

Found RM1 and RM 3. Searched for RM 2 but did not find. Did not search for the azimuth mark. No poison ivy today, but lots of plants with thorns and stickers. Good that it was cold today, so I had to wear thick clothing, or I would have been scratched badly, especially searching for RM 2 and RM 3.

About a 20 minute walk from Route 448, straight up the trail that you can pick up from the stone bridge, or from going around the gate across the car road and walking towards the trail. The coordinates for the car road are accurate. After about 5 minutes on the trail, you'll see the blue "Buttermilk Hill" signpost, and you'll be on the only trail from that point, so it's very simple to reach the summit. I would estimate that the trail is about a mile long, and there is a gain of about 250 feet in elevation from Route 448. For a shortcut, when you're close to Buttermilk Hill's peak, look for a sign "Parking 2." Take the grassy trail to your right, and you'll be at the benchmark within a minute.

The history of this benchmark is still sinking in. The benchmark was set by Ferdinand Hassler who was born in Switzerland in 1770, six years before the Declaration of Independence was written, and who was the first superintendent of the US Coast Survey, appointed in 1816. The property on which the hill is located was once owned by John D. Rockefeller - who was born six years after the benchmark was set; early recovery entries on the NGS datasheet document the owners of the property before Rockefeller - but the land is now owned by New York State and is open to the public.

[Photos:]
photoButtermilk Drill Hole
photoButtermilk Plaque
photoButtermilk Post
photoButtermilk Parking 2 sign
photoButtermilk and TT57K Setting
photoButtermilk RM 1 Disk
photoButtermilk RM 1 Setting
photoButtermilk RM 3 Iron Rod
photoButtermilk RM 3 Setting
photoButtermilk with 1000 Find Coin

Recovered in good condition.

I've had this on my radar for quite some time, and today was the day! I parked just a little further up the road than Gungadoy because there were already a lot of cars there, so I figured the drivers knew what they were doing-- 41 06.582 073 49.211. I went down the path near the bridge to the crushed rock road, passed under the bridge, and headed for GZ. As you come to the cow's watering station (complete with cows today!), just head straight in, don't turn right. Shortly you will see a blue sign marker for Buttermilk Hill. I went up quite aways, then saw a trail that turned uphill. I took it, and when it bent around, I bushwhacked the last 400 feet or so to the benchmarks. I needn't have--I saw the grassy two-track road heading back out and followed it to the crushed rock road to walk back to the car. No bushwhacking needed here--just follow the road and turn right up the track when you are a hundred or so feet away. It was .5 miles uphill as the crow flies, and I think it was about a mile and a half round trip in the end. I went up pretty early, and on my way back, there were a number of runners jogging up the hill--I was bathed in sweat just from walking it!

My phone actually read 2 feet when I found the the benchmarks! It was really a thrill to find this historic drill hole! Wow, I just loved it! It's too bad the view is so overgrown that you can't really quite imagine what Ferdinand Hassler saw as he surveyed the area. This is a must-do for anyone interested in benchmarks! It's a piece of history you can touch! This benchmark is very accessible, and anyone interested should come find it.

[Photos:]
photoOn the right track
photoExcellent coordinates
photoLX4113 BUTTERMILK
photoNice pair
photoI was there
photoThe outcrop

Feel a little guilty logging this one, as I am local and just got into benchmarks. Can't quite appreciate this one yet.

[Photos:]
photoimage

I had read about this BM a while ago a decided next time I was in the area I would stop by and visit. Well, today was the day. On a trip from S. Florida to Boston I decided to drive over from my stop in NJ.
With a couple of relatives we hopped in the car and headed up to Tarrytown and GZ. Not sure where to go in we start a this big fortress looking gate and it turned out to be the back of the Rockefeller's property. We spoke to the guards, very nice guys. I showed them on the Iphone where I was trying to go, Buttermilk, and they told me it's called Buttermilk Hill. They said to park along side the road by an entrance to the property and walk up the road.
Parking is at N41 06.548 W073 49.217. (NY State Highway 448 is same as Bedford Road)
We made the way up the hill, make sure to go around a few curves to the highest point. Off the main road to the right is an unkept road/path that goes to GZ. It was very overgrown today with a little bit of poison ivy over the BM.
Wow, I'm glad I made this journey. A must do.

[Photos:]
photoGungadoy at GZ with BM's.
Surrounded by Poison Ivy.
photoLX4113 GPS
photoLX4113-BUTTERMILK-2-20140804

This was the main stop for today. I was visiting my brother in Connecticut and made the trip over to see this monumental benchmark. The granddaddy of them all! We stopped in Hawthorne for lunch before heading over here. As we drove up and got close, I became really excited. Then I got out of the car and found it quickly. Awesome! I cannot believe something this old is still around to document surveying history. I took several pictures before leaving. WOW! Glad I got the opportunity to see this in person.

[Photos:]
photoBoth marks
photoCloseup with Indiana Benchmarking Series coin
photoPosing at Buttermilk

WOW!! I'm not an avid benchmarker like some of my geocaching friends, but to say that I have now been to the "Holy Grail" of benchmarks is an amazing feeling. We were a bit concerned coming in that we were going to be chased off the property before getting a chance to see it but a friendly wave from a passing car told us that they had no issues with us being there. The hike up to the spot was pretty tame, if a little tiring. The area is completely overgrown and my phone, which was the acting GPSr, decided it had had enough and decided to shut itself off when we were still about 50 feet from the mark. We made a sweep around the area and found Reference Mark #3 completely by accident so we knew we were in the right place. Backtracking a bit, my brother, Team Duckman, headed in the initial direction we were walking before my phone decided to make like an opossum, and soon enough was on top of Buttermilk. The magnitude of the find took a moment to set in, but looking at what's left of that original mark, I suddenly felt the history pour in. This was the oldest surviving triangulation station. The person responsible for this was appointed by Thomas Jefferson to put it here....you don't get much closer to greatness than that.

[Photos:]
photoPlaque outside the property
photoBUTTERMILK!

Been to Buttermilk Hill many times and found this benchmark long ago before I discovered geocaching. Visited the site again today so I'm officially logging the find! Neat place.

I never would have stumbled on this withoutthe coords. They were right on. Right in the middle of nowhere for the year it was placed! Got a great pic too.

[Photos:]
photobuttermilk oldest

Made the journey today to find this old benchmark.

[Photos:]
photoButtermilk Benchmark 009

We thought that more people would have visited this oldest benchmark since it received some publicity and a plaque along the road near the site. Now that the area has become a state park, permission is not needed to hike or horseback on the grounds. On the day we arrived there were people all around but no one we talked with knew anything about this historical mark. Geofun2007 owns a geocoin commemorating this benchmark which we discovered in a cache. Geofun's goal was to have their coin photographed at the actual benchmark. We thought that would be fun too and make an interesting side trip on our way to Ocean City NJ...so that's what we did. The coin is very shiny though and lacks detail whether or not I used the camera's flash. This was a very interesting area along the Hudson and we're glad we had the opportunity to visit. Hope you enjoy the photos.
rscarr2

[Photos:]
photocacher, coin, GPSr & plaque
photohistoric benchmark
The historic benchmark in the lower right with geocoin to its left, GPSr, and newer benchmark disk in upper left corner.
photoanother view
photoleaves around old mark
photocoin on GPSr

Found this with Papa Bear as he describes in his log. A very successful adventure into NYC to visit a very unique mark. Management of the land is in the process of being transferred to the State of New York, eventually allowing more ready access to this point. Many thanks to the kind folks at Greenrock Corporation, particularly Jerry, for their cooperation and assistance.

Having measured to each of the reference marks with a Leica Robotic Total Station, we can note that the locations of reference marks 1 and 2 were found to be consistent with their published values, while reference mark 3 was located at geodetic azimuth 293 degrees, 53 minutes, a distance of 14.883 meters.

As Papa Bear noted, the azimuth mark was also found. Due to intervening tree growth, we were not able to measure to it, but after plotting its approximate position on a Google orthophoto, it appears to be about 0.318 mi. (1680 feet) from the station mark, near one of three cottages on the property.

[Photos:]
photoField Computer for Leica Robotic Total Station
The screen shows Buttermilk in the center and the orientation of the RM's around it. Once we found one, the rest were easy!

The station, azimuth mark and all reference marks were recovered in good condition.

This recovery was a joint project of myself and [url=http://forums.groundspeak.com/GC/index.php?showuser=754612]Holtie[/url]. Holtie came down from Vermont with his wife for a quick afternoon and night visit to New York City, and this morning we drove up to the Rockefeller Estate in Tarrytown NY where the station is located. Why would someone drive down all the way from Vermont on a snowy day to find a mark in the New York area? Simple, BUTTERMILK is the oldest surviving triangulation station in the U.S. and it was set in 1833 by Ferdinand Hassler, who was appointed by Thomas Jefferson to be the first director of the Coast Survey (which became the Coast and Geodetic Survey and is now the NGS). See the [url=http://celebrating200years.noaa.gov/foundations/spatial/side1_spatial.html]NOAA article on BUTTERMILK[/url].

Holtie and I got the idea for this recovery when a link to the above NOAA article was posted in a thread on the Benchmarking forum about a couple of months ago (see [url=http://forums.groundspeak.com/GC/index.php?showtopic=151361]NOAA's 200th anniversary[/url]). We followed up with some serious plans and today we followed through with the recovery. Holtie deserves much of the credit for the work on the ground. As a Licensed Land Surveyor, he brought his tools and expertise which made the recover a "piece of cake" as we like to say.

We are also indebted to Jerry, the very helpful security officer at the estate. He not only said, "sure you can go after it", but he checked out the site last week and even drove up early this morning to make sure the road was passable after last night's 6 inches of snow. He then drove up with us to the site when we got there and even brought a shovel along to help clear the snow from the ground. He said at one point that we were the 5th party he has guided to the mark in the 39 years he has worked there. He is a vast repository of the institutional wisdom that only a security officer would have.

The pictures tell the story. As we drove in, we first stopped to find the azimuth mark, which Jerry had never seen. But he quickly recognized the description of its location - "on top of a concrete pedestal, one of two across an old road". He seemed to enjoy finding the disks as much as we did.

We then drove to the top of the hill where the station is located. We took what he called the "hard road" up, because with the recent weather, the "easy road" was iced over. He had earlier placed a log on the rock ledge where the station is located so we could find it after last night's 6 inches of snow. Thanks Jerry.

Holtie moved the log out of the way and scraped the snow away and [u]voila![/u] there it was. BUTTERMILK is concrete filled hole in the rock ledge about 2 1/2 to 3 inches in diameter with a 3/4 inch iron rod imbedded in it. A USGS disk is set in the same ledge about a foot away. It was set in 1932, almost 100 years after the original mark was set.

While Holtie was working on uncovering the station mark and getting his equipment set up, I found (with Jerry's direction) Reference mark #3, another iron bolt which was set in a boulder at the side of the clearing. This too was found immediately after clearing off the snow. With the station mark and this reference mark now found, Holtie could set up his equipment which would direct us to the exact locations of the other two reference marks. Jerry had never seen the other two disks and didn't know they were there; they were each about 50 feet from the station in the brambly underbrush. But Holtie found first RM # 2 and then RM #1 in quick succession with the help of his equipment. I said "Hey with that stuff, this is too easy, why don't I have that stuff?" Holtie said "Because it cost $32,000!" Wow!

[This entry was edited by Papa-Bear-NYC on Wednesday, February 28, 2007 at 6:38:20 PM.]

[Photos:]
photoLX4113 BUTTERMILK AZ, Mt. Pleasant, NY
Looking up the road with the two concrete pedestals, one on either side, and the cottage beyond.
photoLX4113 BUTTERMILK AZ, Mt. Pleasant, NY
Holtie at the azimuth mark
photoLX4113 BUTTERMILK AZ, Mt. Pleasant, NY
The azimuth mark on the top of the pedestal.
photoLX4113 BUTTERMILK AZ, Mt. Pleasant, NY
The azimuth mark, closeup.
photoLX4113 BUTTERMILK, Mt. Pleasant, NY
The site of the station mark. The log was placed on the rock ledge before the snow came.
photoLX4113 BUTTERMILK, Mt. Pleasant, NY
The station (the iron rod in the hole on the left) and the USGS disk on the rock ledge.
photoLX4113 BUTTERMILK, Mt. Pleasant, NY
photoLX4113 BUTTERMILK, Mt. Pleasant, NY
The hole is between 2 1/2 and 3 inches in diameter and is slightly irregular. It was made with a cold chisel. Note that the measuring tape is aligned a 1" on the left.
photoLX4113 BUTTERMILK USGS disk, Mt. Pleasant, NY
The USGS disk, placed in 1932 is just under 1 foot from BUTTERMILK.
photoLX4113 BUTTERMILK USGS disk, Mt. Pleasant, NY
The USGS disk, just under 1 foot from BUTTERMILK.
photoLX4113 BUTTERMILK USGS disk, Mt. Pleasant, NY
The USGS disk, closeup. The stamping is "TT57K 1932".
photoLX4113 BUTTERMILK, Mt. Pleasant, NY
Holtie sets up his tripod. His wife Lisa lends a hand.
photoLX4113 BUTTERMILK, Mt. Pleasant, NY
Holtie and Papa Bear at the station.
photoLX4113 BUTTERMILK RM #3, Mt. Pleasant, NY
RM #3 is set in the bolder at the edge of the clearing.
photoLX4113 BUTTERMILK RM #3, Mt. Pleasant, NY
Just under a bit of snow.
photoLX4113 BUTTERMILK RM #3, Mt. Pleasant, NY
photoLX4113 BUTTERMILK RM #3, Mt. Pleasant, NY
photoLX4113 BUTTERMILK RM #3, Mt. Pleasant, NY
The station mark (with several of our party) seen through the brush from RM #3,
photoLX4113 BUTTERMILK RM #3, Mt. Pleasant, NY
Setting up to measure from the station to RM #3. The device sitting on the mark is a reflecting prism that allows his equipment to determine an accurate distance and (relative) angle to this mark from the station.
photoLX4113 BUTTERMILK RM #2, Mt. Pleasant, NY
Holtie uncovers RM #2.
photoLX4113 BUTTERMILK RM #2, Mt. Pleasant, NY
RM #2.
photoLX4113 BUTTERMILK RM #2, Mt. Pleasant, NY
RM #2, closeup.
photoLX4113 BUTTERMILK RM #1, Mt. Pleasant, NY
Measuring RM #1
photoLX4113 BUTTERMILK RM #1, Mt. Pleasant, NY
RM #1.
photoLX4113 BUTTERMILK RM #1, Mt. Pleasant, NY
RM #1, closeup.
photoLX4113 BUTTERMILK, Mt. Pleasant, NY
One last photo op with Holtie, Jerry and Papa Bear.
photoLX4113 BUTTERMILK Plaque, Mt. Pleasant, NY
The historic plaque on Bedford Road.
photoLX4113 BUTTERMILK Plaque, Mt. Pleasant, NY
The historic plaque on Bedford Road, closeup.
photoLX4113 BUTTERMILK, Google Map image, Mt. Pleasant,
This is taken from a Google Map image with our route and the points of interest added.
photoLX4113 BUTTERMILK, Mt. Pleasant, NY
Jerry, the security officer par excellance.

Documented History (by the NGS)

1/1/1833 by CGS (MONUMENTED)
DESCRIBED BY COAST AND GEODETIC SURVEY 1833 (FRH) CENTRE OF STATION IN FIRST INSTANCE WAS MARKED BY DRILLING A HOLE OF 2-1/2 INCHES IN DIAMETER AND 10 INCHES DEEP INTO ROCK WHICH SUPPORTS STAND OF INSTRUMENT. INTO THIS HOLE IT IS DESIGNED TO POUR BRIMSTONE AND TO PREVENT HOLE FROM BEING FILLED BY DIRT, ETC.
1/1/1852 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1852 (EB) POLE WAS NOT STANDING. POINT WAS SECURED BY HOLE DRILLED IN ROCK 3 INCHES IN DIAMETER. STATION IS ON FARM OF DAVID RIDER.
1/1/1868 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1868 (JF) SIGNAL POINT WAS FOUND AS DESCRIBED WITH A POLE STILL STANDING AND PROPPED UP AT ITS BASE BY A PILE OF BOULDERS. FOOT OF POLE RESTED IN A HOLE IN A LARGE FLAT ROCK WHICH WAS CUT WITH A COLD CHISEL 10 INCHES IN DEPTH AND 2 INCHES IN DIAMETER. THIS POINT WAS LEFT IN PERFECT CONDITION AND SECURE AS FOUND.
1/1/1881 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1881 (FRG) THIS STATION IS IN WESTCHESTER COUNTY, MOUNT PLEASANT TOWNSHIP, 3 MILES NNE OF TARRYTOWN, AND IS BEST REACHED BY BEDFORD AVE. INQUIRE FOR JOHN GIBNEYS FARM. THIS LIES ON R OF ROAD AND HOUSE IS ABOUT 200 YARDS FROM IT. STATION IS ON SOUTHERN SUMMIT OF BUTTERMILK HILL. SIGNAL POLE WAS FOUND STANDING AND PROPPED UP BY A PILE OF BOULDERS. FOOT OF POLE RESTED IN A HOLE AND IN LARGE FLAT ROCK WHICH WAS CUT BY A COLD CHISEL, 10 BY 2 INCHES.
1/1/1897 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1897 (JBB) STATION WAS RECOVERED. MARK WAS IN GOOD CONDITION. SIGNAL POLE ABOUT 45 FEET HIGH WAS ERECTED. LINE WAS OPENED TO HOOK MT. 2.
1/1/1906 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1906 (FEW) EXTRACT FROM LETTER OF FRANK E. WINDSOR, DIVISION ENGINEER, BOARD OF WATER SUPPLY, CITY OF NEW YORK, WHITE PLAINS, NEW YORK., DATED JULY 17, 1906--ONE OF OUR PARTIES HAS FOUND THE OLD STATION AT BUTTERMILK BUT THE VIEW FROM THIS POINT TO THE NORTH AND NORTHEAST IS NOW SERIOUSLY OBSTRUCTED BY TWO WATER TANKS UNDER CONSTRUCTION HERE. ADDITIONAL TIES, AS FOLLOWS HAVE BEEN TAKEN TO POINTS NOW ON THE GROUND--THE TIE POINT ON THE LARGER TANK IS A CROSS (X) MARKED ON THE HEAD OF THE 15TH RIVET FROM THE TOP OF THE LOWER PLATES, EAST ROW OF RIVETS, AND THE LAP JOINT IS THE ONE ON THE SOUTH SIDE OF THE TANK, DISTANT 19.33 FEET. TIE POINT ON THE SMALLER TANK IS ON THE LOWER SOUTHERLY BOLT IN THE LADDER CONNECTION WITH THE TANK PLATES, DISTANT 25.02 FEET.
1/1/1932 by CGS (SEE DESCRIPTION)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1932 (CAE) A THREE-INCH DRILL HOLE WAS FOUND IN LEDGE ROCK ON HIGHEST PART OF N HILL OF RIDGE KNOWN AS BUTTERMILK HILL WHICH IS ON ESTATE OF JOHN D. ROCKEFELLER. THERE HAVE RECENTLY BEEN EXCAVATING OPERATIONS IN THIS AREA AND NOT ONLY ABOUT 3 FEET OF LEDGE IS BARE AND THIS IS ALMOST FLUSH WITH SURROUNDING GROUND. DRILL HOLE WAS FOUND TO BE FILLED WITH CEMENT WITH A 3/4-INCH IRON PIPE IN CENTER WHICH PROJECTS ABOUT 1 INCH ABOVE ROCK. A REFERENCE MARK WAS ALSO FOUND WHICH WAS NOT MENTIONED IN DESCRIPTION. THIS CONSISTS OF A 1/2-INCH IRON BOLT LEADED IN A DRILL HOLE IN A BOULDER. ACCORDING TO INFORMATION FROM U.S. ENGINEERS THIS STATION WAS RECOVERED AND REMARKED IN JULY 1906 BY FRANK E. WINDSOR OF NEW YORK STATE SURVEY BOARD OF WATER SUPPLY, CITY OF NEW YORK. A STANDARD U.S.G.S. BENCH MARK WAS FOUND CEMENTED IN A DRILL HOLE 1 FOOT S 80 DEG W FROM STATION. IT WAS STAMPED TT57K 1932, WHICH WAS PLACED BY C.B. KENDALL, U.S.G.S. IN 1932. INFORMATION REGARDING ABOVE CAN BE HAD BY WRITING TO STANLEY J. HORN, 1ST. LIEU. 29TH ENGINEERS, FORT SCHUYLER, NEW YORK.
1/1/1932 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1932 (CAE) STATION IS ON N HILL OF RIDGE KNOWN AS BUTTERMILK HILL, WHICH IS ON ESTATE OF JOHN D. ROCKEFELLER, ON HIGHEST PART OF HILL, AND NEAR FORKS OF A ROAD UP HILL WHICH IS LITTLE MORE THAN A TRAIL AT THIS PART. MARK IS A 3-INCH DRILL HOLE FILLED WITH CEMENT WITH A 3/4-INCH IRON PIPE IN CENTER AND EXTENDING ABOUT 1/2-INCH ABOVE THE SURFACE OF ROCK, IN AN OUTCROPPING LEDGE WHICH IS FLUSH WITH SURROUNDING GROUND AND BARE PORTION BEING ABOUT 4 FEET SQUARE. STATION IS SURROUNDED BY TREES AND BRUSH ABOUT 25 FEET HIGH. THERE IS A RESERVOIR FOR HURTHORN WATER DISTRICT BEING CONSTRUCTED ABOUT 300 METERS E OF STATION. THERE IS A STANDARD U.S.G.S. BENCH MARK MARKED TT57K 1932 CEMENTED IN SAME LEDGE 1 FOOT S 80 DEG W OF STATION. REFERENCE MARKS NOS.1 AND 2 (STAMPED NO.1 AND NO.2 1932) ARE STANDARD BRONZE DISKS CEMENTED IN DRILL HOLES IN OUTCROPPING ROCK WHICH IS ALMOST FLUSH WITH SURROUNDING GROUND. REFERENCE MARK NO.3 IS IN IRON BOLT LEADED IN A DRILL HOLE IN TOP OF A 3-FOOT BOULDER WHICH IS AT EDGE OF ROAD. HEIGHT OF SIGNAL ABOVE STATION MARK - 9 METERS.
1/1/1932 by CGS (MARK NOT FOUND)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1932 (FLG) STATION WAS SEARCHED FOR BUT COULD NOT BE FOUND. HILL IS NOW ON ESTATE OF MR. J.D. ROCKEFELLER. IN ABOUT 1904 TWO LARGE WATER TANKS WERE ON THIS HILL UPON LARGE CEMENT PIERS. WHEN THESE WERE REMOVED A FEW YEARS AGO, PIER FOUNDATIONS WERE BLASTED OUT AND STATION WAS UNDOUBTEDLY LOST.
1/1/1934 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1934 (DBM) STATION WAS RECOVERED SUBSTANTIALLY AS DESCRIBED BY C.A. EGNER, 1932. NOTE--CARE SHOULD BE TAKEN NOT TO CONFUSE TRIANGULATION POINT (WHICH IS A 3/4-INCH PIPE CEMENTED IN ROCK) WITH A U.S.G.S. BENCH MARK DISK WHICH IS ABOUT A FOOT SW OF STATION.
1/1/1938 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1938 (CDM) STATION WAS FOUND AS DESCRIBED BY C.A. EGNER, 1932. STATION IS ON N HILL OF RIDGE KNOWN AS BUTTERMILK HILL, ON JOHN D. ROCKEFELLER ESTATE, ON HIGHEST PART OF HILL, AND NEAR FORKS OF A ROAD WHICH IS LITTLE MORE THAN A TRAIL AT THIS POINT. MARK IS A 3/4-INCH IRON PIPE SET WITH CEMENT IN A 3-INCH DRILL HOLE IN LEDGE ROCK WHICH IS ALMOST FLUSH WITH SURROUNDING GROUND. BARE PART IS ABOUT 4 FEET SQUARE. STATION IS SURROUNDED BY TREES ABOUT 25 FEET HIGH. REFERENCE MARKS NOS.1 AND 2, STAMPED NO.1, 1932 AND NO.2, 1932, ARE STANDARD BRONZE DISKS CEMENTED IN DRILL HOLES IN LEDGE ROCK WHICH IS ABOUT FLUSH WITH GROUND. REFERENCE MARK NO.1 IS SE OF STATION AND REFERENCE MARK NO.2 IS SW OF STATION. REFERENCE MARK NO.3 IS AN IRON BOLT LEADED IN A DRILL HOLE IN A 3-FOOT BOULDER, WNW OF STATION. AZIMUTH MARK IS APPROXIMATELY 1/4 MILE SW OF STATION IN TOP OF WESTERLY OF TWO CONCRETE PEDESTALS, 31 PACES S OF A MACADAM ROAD, AT EDGE OF A ROW OF PINE TREES. THERE IS STANDARD U.S.G.S. DISK STAMPED TT57K 1932 CEMENTED IN LEDGE 0.995 FOOT S 80 DEG W OF STATION. TO REACH STATION FROM JUNCTION OF U.S.9 AND N.Y.117 IN NORTH TARRYTOWN, GO NE ON 117, 0.35 MILE TO JUNCTION WITH 9A (U.S.). CONTINUE STRAIGHT ON 117, 1.05 MILES TO T-INTERSECTION AT POCANTICO HILLS. TURN L AND GO 1.2 MILES. TURN R AT STONE ENTRANCE GATEWAY OF ROCKEFELLER ESTATE, AND GO 0.25 MILE TO LOCKED GATE. CONTINUE STRAIGHT 0.2 MILE TO T-JUNCTION ON TOP OF RIDGE. TURN L ON CINDER ROAD. CONTINUE 0.2K MILE TO Y. TURN R AND GO 0.05 MILE. TURN R ON DIRT ROAD AND CONTINUE 0.05 MILE TO CLEARING ON TOP OF HILL AND STATION. STATION MARK IS AN IRON PIPE SET IN LEDGE ROCK. REFERENCE MARKS NOS.1 AND 2 ARE STANDARD BRONZE DISKS SET IN OUTCROPPING BEDROCK. REFERENCE MARK NO. 3 IS AN IRON BOLT SET IN A BOULDER. AZIMUTH MARK IS A STANDARD DISK IN TOP OF CONCRETE PEDESTAL. NOTE--25-FOOT STAND SEES MAIN SCHEME STATIONS AND AZIMUTH MARK. PERMISSION MAY BE OBTAINED FROM SUPERINTENDENT OF ESTATE, ALTHOUGH IN 1938 IT WAS NECESSARY TO DEAL WITH MR. ROCKEFELLER IN NEW YORK CITY. HEIGHT OF LIGHT ABOVE STATION MARK 23 METERS.
1/1/1939 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1939 (MAH) ALL MARKS WERE RECOVERED AS DESCRIBED BY C.D. MEANEY IN 1938. STATION WAS NOT OCCUPIED IN 1939 AND DISTANCES AND DIRECTIONS WERE NOT CHECKED.
1/1/1964 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1964 (GB) STATION WAS RECOVERED IN GOOD CONDITION. IT IS LOCATED ON A HIGH HILL ALMOST DUE WEST OF THE HAWTHORNE TRAFFIC CIRCLE. STATION IS A 3/4 IN PIPE CEMENTED IN ROCK ON THE HIGHEST PART OF THE NORTH HILL ON THE ESTATE OF JOHN D. ROCKEFELLER, JR. THIS STATION MAY BE DRIVEN TO WITH ALMOST ANY VEHICLE. GO TO THE ROCKEFELLER ESTATE OFF ROUTE 117 IN NORTH TARRYTOWN. OBTAIN PERMISSION AND KEY TO GATE.
1/1/1966 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1966 (JLC) THE STATION AND ALL THE MARKS WERE RECOVERED AND FOUND TO BE IN GOOD CONDITION BUT THERE WAS A DISCREPANCY IN THE DISTANCES AND DIRECTIONS TO THE MARKS AS COMPARED TO ANY PREVIOUS MEASUREMENTS AND OBSERVATIONS. THE AZIMUTH MARK IS NO LONGER VISIBLE FROM THE GROUND BECAUSE OF DENSE TREE GROWTH IN THE AREA OF THE STATION. A NEW DESCRIPTION FOLLOWS. THE STATION IS LOCATED IN THE TOWN OF MOUNT PLEASANT ABOUT 2.5 MILES EAST OF THE EAST SHORE OF THE HUDSON RIVER, 2.2 MILES EAST-NORTHEAST OF THE VILLAGE OF NORTH TARRYTOWN, 1.7 MILES SOUTHWEST OF THE VILLAGE OF HAWTHORNE STATION, 1.3 MILES SOUTHEAST OF THE SOUTHEAST SHORE OF POCANTICO LAKE AND ON PROPERTY OWNED BY MR. JOHN D. ROCKEFELLER. TO REACH THE STATION FROM THE JUNCTION OF U.S. HIGHWAY 9 AND STATE HIGHWAY 117 IN NORTH TARRYTOWN, GO NORTHEAST ON STATE HIGHWAY 117 FOR 0.35 MILE TO A CROSSROAD. CONTINUE STRAIGHT AHEAD ON STATE HIGHWAY 117 FOR 1.15 MILES TO A CROSSROAD AND A SMALL PARK ON THE RIGHT IN THE VILLAGE OF POCANTICO HILLS. (TO GET KEY TO THE STATION, TURN RIGHT HERE AND GO SOUTH FOR 0.2 MILE TO THE ENTRANCE TO THE ROCKEFELLER ESTATES HEADQUARTERS, INSIDE THE GATE AND FENCED AREA.) TURN LEFT AND GO NORTHEAST FOR 0.15 MILE TO A SIDE ROAD RIGHT JUST BEFORE REACHING A STONE CHURCH ON THE RIGHT. TURN RIGHT AND GO EAST ON A PAVED ROAD FOR 0.05 MILE TO A LOCKED GATE. PASS THROUGH THE GATE AND CONTINUE EAST ON THE ROAD FOR 0.05 MILE TO A THREE WAY FORK. TAKE THE LEFT FORK AND GO NORTHEAST ON A GRAVELED ROAD FOR 0.2 MILE TO A CROSSROAD. CONTINUE AHEAD ON THE ROAD FOR 0.3 MILE TO A CROSSROAD. CONTINUE AHEAD ON THE ROAD FOR 0.3 MILE TO A REVERSE Y-FORK. CONTINUE IN A NORTHEASTERLY DIRECTION FOR 0.2 MILE TO A FORK, KEEP THE RIGHT FORK AND GO NORTHEAST FOR 0.1 MILE TO A REVERSE Y-FORK. CONTINUE STRAIGHT FOR 0.35 MILE TO A ROAD LEFT.** CONTINUE STRAIGHT AHEAD FOR 0.3 MILE TO A FORK. TURN SHARP LEFT AND GO SOUTHWEST UPHILL FOR 0.05 MILE ON A TRACK ROAD TO THE STATION ON THE LEFT. THE STATION MARK IS A 3-INCH DRILL HOLE FILLED WITH CEMENT WITH A 3/4-INCH IRON PIPE IN THE CENTER WHICH IS FLUSH WITH THE SURFACE OF THE ROCK IN WHICH IT IS SET. IT IS 0.99 FEET EAST OF A U.S. GEOLOGICAL SURVEY DISK WHICH IS STAMPED, TT57K 1932. REFERENCE MARK 1 IS A STANDARD DISK STAMPED NO 1 1932, CEMENTED IN A DRILL HOLE IN OUTCROP WHICH IS FLUSH WITH THE GROUND AND ABOUT 5 FEET LOWER IN ELEVATION THAN THE STATION. REFERENCE MARK 2 IS A STANDARD DISK STAMPED NO 2 1932 CEMENTED IN A DRILL HOLE IN OUTCROP WHICH IS FLUSH WITH THE GROUND. IT IS ON THE SOUTHWEST SLOPE OF THE HIGHEST PART OF THE HILL AND ABOUT 2 FEET LOWER IN ELEVATION THATN THE STATION. REFERENCE MARK 3 IS A 3/4-INCH IRON BOLT LEADED IN A DRILL HOLE IN A 3-FOOT BOULDER WHICH PROJECTS 3 FEET ABOVE THE GROUND AND THE SAME ELEVATION AS THE STATION. THE AZIMUTH MARK IS A STANDARD DISK STAMPED BUTTERMILK 1938 SET IN A DRILL HOLE IN THE TOP CENTER OF A 21 X 21 X 52-INCH CONCRETE PEDESTAL. IT IS 20 FEET NORTHWEST OF A TRACK ROAD. **TURN LEFT AND GO WEST ON A TRACK ROAD FOR 0.05 MILE TO AN OLD PAVED ROAD. TURN LEFT AND GO SOUTHWEST ON THE OLD PAVED ROAD THROUGH A MEADOW FOR 0.1 MILE TO 2 CONCRETE PEDESTALS WHERE THE PAVED ROAD ENDS AND A TRACK ROAD CONTINUES BETWEEN THE PEDESTALS AND THE AZIMUTH MARK IN THE PEDESTAL ON THE RIGHT. HEIGHT OF LIGHT ABOVE STATION MARK 87.4 FEET.

Control Text

  • The horizontal coordinates were established by classical geodetic methods and adjusted by the National Geodetic Survey in January 1999.
  • The NAVD 88 height was computed by applying the VERTCON shift value to the NGVD 29 height (displayed under SUPERSEDED SURVEY CONTROL.)
  • The Laplace correction was computed from DEFLEC99 derived deflections.
  • The geoid height was determined by GEOID99.

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