Modern information-storage systems are highly wonderful. But the most capacious of them (disks and tapes) still depend on mechanical scanning. Daedalus is dreaming up a read-only high-volume storage system with no moving parts.

His starting point is fibre optics. A mere gram of glass, in the form of fibre 1 micrometre in diameter, would extend about 500 km. Lay a binary code along it at 1 bit/micrometre, and it would store 500 gigabits — an unprecedented solid-state information density. You could write on the fibre as it was being drawn, by passing it through an ion beam modulated with the information to be stored. The ions would diffuse into the hot surface, and would be fixed when the fibre cooled to room temperature. Cunningly, Daedalus wants these ionic impurities to be fluorescent. Illuminated by light of one frequency, they will re-radiate it at a second frequency.

To read the fibre, Daedalus will simply send a short intense optical pulse down it. As the pulse passes each ‘bit’ of data, it will generate a fluorescent pulse, which will travel back along the fibre to a detection unit at the pulse-injector. The returning pattern of fluorescence pulses contains all the information in the fibre.

In this simple design, the loss of energy to fluorescence would rapidly damp out the most intense interrogation-pulse. But fibres these days can have optical gain. An erbium-doped fibre acts as a distributed laser; illuminated with a suitable pump radiation, it actively amplifies the pulses travelling along it. Indeed, the data-points in the new fibre might even be encoded as spots of erbium doping.

Daedalus's Fibre Read-Only Memory, or FROM, will hold its information unalterably and permanently, as a pattern of impurity doping along its length. Simple, fast, capacious and secure, FROMs will form the basis of libraries and archives of all kinds. Unlike disks or tapes, they cannot deteriorate or go wrong, nor become unplayable by format changes to their reading mechanism. FROMs will be entrusted with the most fundamental, unchanging information: historical and public records, encyclopaedias, runs of scientific journals, great works of art. Authors and artists will no longer be satisfied with mere paper publication or world-wide broadcast distribution. The ultimate cachet of worth will be to have one's creation immortalized in the only truly time-proof form — a FROM.