All existing classification systems required that these large tomes and small leaflets share the same shelf. As a result, not only did the smaller documents suffer damage, but there was also an unacceptable amount of wasted “air” space above each shelf. Clearly, if that space could be utilized efficiently, then it would be possible to recover a substantial area for more books. We certainly felt the need to save space, because any additional bookcases in the apartment would make it impossible to move around comfortably.

Somebody humorously suggested a Compactus - a rather unwieldy and very expensive electrical shelving device which moves book stacks on a track, pushing several stacks together until an item is needed from a unit in the middle, in which case the specific shelves would open up by shoving all the adjacent stacks out of the way. Yes, that picture in your mind’s eye of Samson pushing the columns seems quite appropriate here. That idea was dismissed as being unfeasible. After all, we wanted to live in this house!