A Surveyor Looks at the Washington, DC Planning Map
On page 349 of Secret Architecture, David Ovason describes the layout of Washington DC -
"It was engineered over 200 years ago, when either Ellicott or L'Enfant drew a line from the top of a wooded hillside, and directed it toward a specific point of sunset. From this single line, the planner subtended another which ran due west from the hill. At a certain point along the second line, he drew across it, at right angles, a third. He extended this so that it cut the first line - the sunset line. In this way he formed a triangle on the earth.
Look at the image above that shows the bend in Penn Ave. Ovason is suggesting that the layout of the city was begun from the Capitol Building location, using the segment of Penn Ave between that and the White House location. (Remember that some of the Mall area was once a creek.)
The image above is taken from L'Enfant's June plan that was revised and never used. Here we see the three lines that Ovason refers to. The line between the CB and the WH is supposedly aligned with the Aug 10th sunset. If you look you will see that the map is symmetrical around the east west line from the CB to the west, so that the angle made by Maryland Avenue is the same as that made by Penn Ave there. If you know astronomy, you know that the sun sets on Penn Ave in May as well in August, and that it sets over Maryland Ave in Feb and Nov. Ovason never mentions Maryland Avenue.
In Ovason's story, the first line that is shot is from the CB to the northwest and the White House, the second line that is shot is to the due west. Only then is a line projected due north from some location toward the White House again.
If you look at two images up, you will notice that it is a planning map which features a lot of landscaping. The image above shows that as of 1820, there still was no solid ground where two of the lines cross. Notice that he never mentions setting up a meridian (n-s) line at the CB location. THAT would be one of you first lines. There and at the WH. Those could be set up independently of any diagonal lines.
The main question that arises is, if that segment of Penn Ave is the base angle of the map, which we see mirrored in Maryland Ave, how were the south east and north west diagonal angles determined? I submit that when you look at a straight line from G'town to the East Branch, you can see that is the base line, and that the CB has been moved from it's ideal location. I submit that the prime viewing place was not of sunsets from the CB, but of sunrises from Georgetown.
In his 1898 book "The Canon", William Striling wrote that the rhombus and the cross formed the basis of the Milan Cathedral plan. He suggests that the rhombus and cross symbolize the Royal Wedding, just as the two inter-laced triangles of the hexagraam do.
If you look at Penn, Mass, Rhode Island and NY Aves crossing each other at 16th Street, you can see the beginning of a rhombus grid. You can also see that the map is 'regular' around the WH, yet the streets near the CB do not fit that grid. The suggestion is that since the CB was moved, and since many streets are tied to the CB location, the 'dislocation' of the CB has mis-aligned much of the southeast section of the city.