were selected and collated by the BBC Domesday project based in Bilton House in West Ealing. Pre-mastering of data was carried out on a VAX-11/750 mini-computer, assisted by a network of BBC Micro microcomputers. The discs were mastered, produced, and tested by the Philips Laservision factory in Blackburn, England. Viewing the discs required a BBC Master AIV - an Acorn BBC Master expanded with a SCSI controller and the 65C102 "Turbo" co-processor - which controlled a Philips VP415 LaserVision laserdisc player. The user interface consisted of the BBC Master's keyboard and a trackball (more specifically the Marconi RB2 Trackerball rebranded by Acorn). The enhancements provided by the Philips VP415 permitted computer control and access to data stored on the discs. The project was split over two laserdiscs: The Community Disc contained personal reflections on life in Britain and is navigated on a geographic map of Britain. The entire country was divided into blocks that were 4 km wide by 3 km long, based on Ordnance Survey grid references. Each block could contain up to 3 photographs and a number of short reflections on life in that area. Most, but not all, of the blocks are covered in this way. In addition more detailed maps of key urban areas and blocks of 40x30 km and regional views were captured, allowing "zoom-out" and "zoom-in" functions. The community disc was double sided, with a "Southern" and a "Northern" side, although country-wide data at the 40x30km level and above was on both sides. The National Disc contained more varied material, including data from the 1981 census, sets of professional photographs and virtual reality-like walkarounds shot for the project. Side 2 of the National disc contained video material. The material was stored in a hierarchy and some of it could be browsed by walking around a virtual art gallery, clicking on the pictures on the wall, or walking through doors in the gallery to enter the VR walkarounds. In addition a natural language search was provided, supported through the application of the Porter stemming algorithm. Supported platforms The application software for the project was written in BCPL (a precursor to C) to facilitate portability between different hardware and software platforms, although the software required additional patches to run on the RM Nimbus version of the system. An Amiga version of the system was considered but not initiated. Preservation In 2002, there were great fears that