It is close, and if you consider Washington as a district there is a meridian exactly 77 degrees west somewhere in there. But I am here eyeballing maps and if the "Washington meridian" is considered the point of the capital it is ~ 1000 feet west of -77.0, should have chosen Stanton park. Seeing as Washington was a planned city I wonder if the capitol point was supposed to be -77.0 west but limitations in surveying accuracy put it where it is. A thousand foot error is not bad for 1800. In fact the very public line at Greenwich is off by ~ 50 feet.

On the subject of eyeballing maps are there any online openstreetmap derivatives that have better cartography tools? (crosshair, lat long at specific point, distance and bearing lines, etc) I probably could install qgis for it, and osmand has a bunch of these tools. but the default osm page sort of sucks here.