The world faces an information "dark age" because so much data is stored digitally, a leading scientist has warned. Professor David Garner, president of the Royal Society of Chemistry, said that wherever possible scientific data should be printed and kept in paper archives to avoid crucial research being lost to future generations.Information stored on computers risked becoming inaccessible because of outdated formats, and paper back-ups were vital to ensure the survival of knowledge, he said.He pointed to a project by the BBC in 1986 to create a multimedia version of the Domesday Book, to mark the 900th anniversary of the 1086 publication.The information was stored on two virtually indestructible interactive video discs that by the 1990s could no longer be read by computers.It wasn't until 2002 that a team at Leeds University created software that emulated the obsolete Acorn Microcomputer system.The Domesday Project has become synonymous with the problems of digital preservation. In contrast, the original Domesday Book, an inventory of England compiled by Norman monks, remains easily available in the National Archives in Kew, London."It was interesting that the original Domesday Book was still available and yet the digital version could no longer be read," said Garner."Technology is moving far more quickly than it was in the 1980s and 1990s, so this kind of issue is going to occur more often. Digital storage has put knowledge in an instantly accessible form, but things really need to be backed up in paper as well."I think the internet is fantastic. But it's really important that we have accessible paper archives. We risk a lot of information being lost without adequate paper copies."Print has the advantage of being technology-independent and so is always going to provide an alternative, safe backup."Digital materials are especially vulnerable to loss and destruction because they are stored on fragile magnetic and optical media which can deteriorate and can easily be damaged by exposure to heat, humidity and short circuits. ..