How accurate was Colvin’s work

Posted in Colvin points on November 10th, 2009

I am often asked “how accurate were Colvin’s measurements”.

Well, based on the extremely small sampling that I have personally re-measured, I would say it varies from better than what is typically obtained today to god awful. The better work appears to be that in which Colvin personally performed the observations and the worst appears to be that which was performed in his absence.

A 1995 report entitled “Kinematics and Dynamics of Strain Accumulation in the Adirondacks {USGS 1434-94-G-2473, Final Report by John Beavan, Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964} details the use of Colvin station marks in helping to determine the movement of the Adirondack Mountain range. A resulting un-intended conclusion of their work is found in the report as follows:

“Conclusion: The 1800’s triangulation surveys of the Adirondacks resulted in horizontal station coordinates precise to about 0.5 m (when selecting the best data available to us). The 1940’s survey resulted in precisions of 0.1-0.2 m. The 1995 GPS data gives precisions estimated at 0.01-0.02 m. The accuracies of the earlier surveys, while commendable for their time, are insufficient to detect deformation associated with the uplift of the Adirondacks.”

Jim Vianna


The Great Corner Revisited

Posted in Crew events on November 3rd, 2009

Under the direction of the Camp Clerk (Mike Webb, L.S.) students from SUNY Ranger School made a return recovery to the “Great Corner” this fall. A detailed write-up can now be downloaded from the “Past Recoveries” page.

Well done Mike,

Lake Tear of the Clouds

Posted in Crew events on September 24th, 2009


Just wanted to say thanks to everyone for another successful recovery. All went well with various points being recovered. The weather could have been better on the summits but at least no serious rain. Check back in a few weeks on the “Past Recoveries” page for a full write up.

Jim Vianna

C. Donald at Lake Tear

Colvin Reports Now Available

Posted in Colvin points on August 5th, 2009


The N.Y.S. Library is in the process of scanning and electronically publishing all of Colvin’s reports to the N.Y.S. Legislators (and the maps found in those reports). A large portion of this work has now been completed and is available for downloading. The scans are in .pdf format and may take a considerable period of time to appear on your computer. I suggest the use of their FAQ page if you encounter problems. You will not be able to bookmark each report as they use a constantly changing URL. The best way to gain access to the downloads is by clicking below, then selecting the “search digital collections” bar located near the top of the page and then type in “Verplanck Colvin” in the search window

Colvin Reports

Measuring Bars ???????

Posted in Colvin points on July 7th, 2009

I first came across these pictures while visiting the Adirondack Research Center of the Association for the Protection of the Adirondacks, now called “Protect the Adirondacks” about two years ago. Having never seen anything like this in the surveying world previously, to say it caught my interest is an understatement. Well, after keeping my ears open, I finally obtained the last Colvin report published for the years 1898-1899 which was edited by fellow crew member Norman J. VanValkenburg and published in 1989. Much to my surprise, therein was found a detailed report on the use of these measuring bars as written by Professor E. A. Fuertes, Director and Dean of the College of Civil Engineering of Cornell University. This report details the Professor’s work at Lake Placid in August of 1897.
While I admit that the following report is an exception rather than the norm for the expected accuracy of Colvin’s work, I find it extremely interesting and worthy of an easy future recovery.

  These two pictures show the crew measuring down the slope of land towards the shore of Lake Placid

 (Note: the use of two instruments in this process)



Here is the actual report as told in Prof. Fuertes own words and as extracted from “REPORT OF THE SUPERINTENDENT OF THE STATE LAND SURVEY OF THE STATE OF NEW YORK FOR THE YEAR 1898” edited by Norman J. Van Valkenburgh , The Adirondack Research Center of the Association for the Protection of the Adirondacks, 1989, first edition.

(Click on the individual page to open it in a larger window for ease of viewing)






 Items worthy of note are: The Professor being upset with the monument being 1 mm out of position, 20 days to go 1,144 feet and a difference in the two runs of 0.002± of a foot.