"in the Reading Room, under the high dome"

The British Museum Reading Room 2006
GNU Free Documentation LicenseThe British Museum Reading Room 2006 - Credit: Unknown
The Reading Room is a round room in the central courtyard of the British Museum, built to house the museum's library. Completed in 1857, it has a diameter of 140 feet (approximately 42.6m) and was inspired by the domed Pantheon in Rome. The Room was originally surrounded with iron bookstacks, and contained three miles (4.8 kilometres) of bookcases and twenty-five miles (forty kilometres) of shelves.

In 1986, the period in which Possession is set, the British Library was housed within the Reading Room, and readers would sit at desks around its wheel-like layout. In 1997 the British Library moved to a new location in St Pancras, and the interior of the Reading Room was carefully restored. In 2000 The Reading Room re-opened, and was made available to all Museum visitors for the first time. At the same time, the museum's Great Court was completed, allowing visitors to move freely around the main floor - and the outside of the Reading room - for the first time in 150 years. From 2007 the Room found a new use, as a home for major exhibitions. It is scheduled to revert to its normal use in 2012.

The British Museum website.