The Nexus Symbol
Anyone who has visited the Cavern will be familiar with the Nexus, an Age which contains many, possibly thousands, of Linking Books. Explorers to the Nexus can only ever access one small room inside which stands the Nexus Terminal.
The interior of the small room with Nexus Terminal
It is unknown how many of these rooms are located within the main Nexus Age, but it would stand to reason that there would be many, many more than the one an individual Explorer visits. It was intended, after all, to be the main way in which the D’ni would travel between various locations of the Cavern with ease, so only having one would seen counter productive.
Explorers will only have access to Linking Books for locations they have registered with the Ki. Registration can be achieved by visiting a location’s Nexus Pedestal (an example can be seen at the top of this entry). All Pedestals hold a Linking Book to the Nexus itself with a small recess on the user’s left hand side. When one places their Ki device into this recess (on or off the hand) the Pedestal will register with the Ki, giving the user access to it via the Nexus from that point on.
Looking at the base of a Nexus Pedestal or the floor of the Nexus Room itself you will be able to make out a crisscrossed, star-like pattern. This pattern seems to represent the Nexus linking network, the intersecting “arms” of the star representing how each location (and Ages, in some cases) are all connected via the Nexus.
This pattern also appears in other locations. It appears on the tiled floor of Bevin at the foot of the large public clock, or Gorahyan, situated there. The reason the pattern is shown here is unclear, but it could be because the D’ni use Ki time regardless of what Age they are in.
Another pattern related to the Nexus that repeats of that of a series of gears. This can be seen clearly on the wall of the Nexus room when one Links in. It can also be seen on the walls of some buildings in the various Cavern neighborhoods, as identified by the images below.
Why the gear pattern appears on these neighborhood houses is unknown. It clearly indicated something related to the Nexus. Perhaps it was where the main workings were located in each neighborhood, or perhaps the person living in that house worked on the Nexus itself.