Flamsteed’s well telescope

John Flamsteed, the first Astronomer Royal at Greenwich, used a 100-foot (30.5m) well on this site to accommodate a very long telescope. The astronomers sat at the bottom of the well and observed stars that passed directly overhead. It was hoped that placing the telescope in the well would make it possible to create a steady long-focus instrument for very fine measurements. Flamsteed made a few observations from here in 1679, but the damp underground conditions soon made the telescope impossible to use.

This reconstructed circle of bricks indicates the approximat site of the well telescope.

[illustration of the telescope]

The telescope is in the Meridian Garden, a place where various historical measuring and observation instruments are concentrated.

The plaque depicts the well where the long telescope built by Astronomer Royal John Flamsteed stood.

The restoration of the well was photographed on the same day Click for a larger image