US Geographic Center

From wikipedia:
In 1918, the Coast and Geodetic Survey found this location by balancing on a point on a cardboard cutout shaped like the U.S. Incredibly, this method was accurate to within twenty miles, but while the Geodetic Survey no longer endorses any location as the center of the U.S., the identification of Lebanon, Kansas has remained.

My guess:
weighted mean...hahaha
B-)

RADAR, post: 374120, member: 413 wrote: From wikipedia:
In 1918, the Coast and Geodetic Survey found this location by balancing on a point on a cardboard cutout shaped like the U.S. Incredibly, this method was accurate to within twenty miles, but while the Geodetic Survey no longer endorses any location as the center of the U.S., the identification of Lebanon, Kansas has remained.

My guess:
weighted mean...hahaha
B-)

Hi Radar, my Nat'l Geographic atlas also shows a square symbol at Lebanon,KS,thanks much.

I am guessing a latitudinal arc with equal areas above and below, then do the same with the long. Hopefully they put more thought into it than the folks who made up the 45 degree north signs, all of which are about 10 miles too far south to be called midpoints of the hemisphere...

See attached pdf from

RADAR, post: 374120, member: 413 wrote: From wikipedia:
In 1918, the Coast and Geodetic Survey found this location by balancing on a point on a cardboard cutout shaped like the U.S. Incredibly, this method was accurate to within twenty miles, but while the Geodetic Survey no longer endorses any location as the center of the U.S., the identification of Lebanon, Kansas has remained.

My guess:
weighted mean...hahaha
B-)

Lebanon? Balogna!

Does American Samoa count? It's so far away from the center it could probably offset New England all by itself.

The Geo center is for the conterminous 48

This is my webpage on the subject and a book is forthcoming. The text portion has already surpassed 80 pages with over 47,000 words. Stayed tuned...

http://www.geographicalcenters.com

J. Penry, post: 374160, member: 321 wrote: This is my webpage on the subject and a book is forthcoming. The text portion has already surpassed 80 pages with over 47,000 words. Stayed tuned...

http://www.geographicalcenters.com

I enjoyed the POI page:

http://www.penryfamily.com/geographicalcenters/inaccessibility.html

The center of gravity method involved cutting out the shape of the figure of something stiff like a piece of plywood. Then drill holes close to the edge all around the edge and insert wires in the holes. Bring all wires to a central point and hang the object and make sure it is level. Then from the same central point hang a plumb bob. This was how the geographical center of North America at Rugby, North Dakota was located by Edward M. Douglas who used a piece of stiff cardboard. There was huge controversy as to the scientific reasoning with this method. Douglas said his finding was not official and before he could make things right, he died. No one knows what Douglas used for the shape of North America. No two people would ever come up with the same shape of North America.

As you mentioned in your work, what exactly is North America is the critical issue. Do islands count? If so, which ones do and which ones don't. I'm not even sure where it stops as you head south from Arizona, let alone somewhere near Greenland.

Does Central America count? The other issue is whether one should count only land mass or include the water boundaries. If one excludes water, then do you exclude the Great Lakes? Another argument is territorial water boundaries since some coastal states include these as part of their state for rights such as fishing.

As I am writing my book, there are some very interesting things that come up such as how to define the shape of a particular region on the earth. If you try to define the center by the center of gravity method with a flat cutout, that in itself is not correct since it is not a curved surface.

In the extreme points of North America, defining the Easternmost and Westernmost points by longitude can get very tricky. If you use the International Date Line it is different than using the 180th meridian. Your eastern and western extremes would actually be across the line in west and east longitudes.

J. Penry, post: 374166, member: 321 wrote: The center of gravity method involved cutting out the shape of the figure of something stiff like a piece of plywood. Then drill holes close to the edge all around the edge and insert wires in the holes. Bring all wires to a central point and hang the object and make sure it is level. Then from the same central point hang a plumb bob. This was how the geographical center of North America at Rugby, North Dakota was located by Edward M. Douglas who used a piece of stiff cardboard. .

I'm pretty sure the above procedure could have been simplified immensely as follows.

Take the cutout and put two holes in it: one near the north edge, one near the east edge;
Put a nail in a wall and hang the cutout from one of the holes, making sure it hangs freely without touching the wall. Using a plumb line or level as plumb or plumb chalk line scribe a vertical line through the center area of the cutout. Repeat by hanging the cutout from the other pole.

The intersection of the two lines is the center of gravity.

The southernmost point is in Florida just south of the official marker that states southernmost point of usa. It was disappointing to look at a map and see more south...

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