the world > the universe > cosmology > science of observation > astronomical instruments > measuring altitude > [noun] > mural arch (2)
Astronomy. Designating or relating to a wall or walled arch set in the plane of the meridian for the alignment of a large quadrant, telescope…
Astronomy. Designating or relating to a wall or walled arch set in the plane of the meridian for the alignment of a large quadrant, telescope…