The TeegsThe In-Teeg and the Out-Teeg
Two huge machines dominate the Core: the Telegressors, or "Teegs" -- iron-foam shells 21 kilometers in diamater, containing complex and mystical machinery that defies human understanding of the Universe. Each Teeg is a one-way gate through normal space, from the Core of its own Lattice World to a corresponding Teeg in one of the eight adjacent Lattice Worlds within the Lattice's two-dimensional matrix. One, the Out-Teeg, operates as a Sender, with its destination defined by the Control Center computers. The other, the In-Teeg, processes matter transmitted from the eight neighbors.
Once a connection is established by the Out-Teeg (an automated process that takes a minimum of seven minutes, assuming no delay of connection exists), any physical material in the Core can be pushed into the Teeg's interface, and will instantly emerge from the In-Teeg in the desginated neighboring Lattice World. The Teeg interfaces, which glow bright green, stretch for 16 kilometers across the Teeg's outer face, leaving more than enough room for large ships to transfer back and forth between Lattice Worlds with ease (indeed, the only practical concern of such ships is the two-kilometer width of the Fluteholes in the Pole Tunnels).
Facing the Teegs, mounted on the outer walls of the Core, are two huge lights, called the Sidelights, which illuminate the interior of the Core, and cast eery spiderlike shadows of the Teegs and Teeg Wires on opposite walls. The first thing a traveller sees, upon entering a Lattice World Core from a Teeg, is that shadow, with the Sidelight glowing in its midst, like an eye.
The Teeg Wires
Though securely connected to the Pole Tunnels, the Teegs also enjoy further stability from a series of thick cables, called Teeg Wires, which stretch from the Teegs' shells to the inside walls of the Core. Seven Teeg Wires space equally around the edge of each Teeg, at an angle of 40° to the Pole Tunnels themselves. They are 600 meters thick, and constructed of the same iron foam as is the Lattice Worlds themselves. Their tensile strength is not great, and their practical value has been called into question by engineers; but considering how little tidal force actually affects the Teegs at their central location within a Lattice World, they seem to do the job (if, indeed, we have guessed their function correctly).
The Teeg Wires offer up some small amount of navigation hazard within a Lattice World's core; despite their minimal occupation of the Core's volume, careless flight has seen more than one vessel wrecked against a Teeg Wire (and, on occasion, the Wire wrecked as well).
1WT and XWT
Granted, that the leap of 5.1 lightyears in a fraction of a second is an amazing feat -- but since the function of the Teegs was discovered, mankind has wondered whether some method exists of specifying a non-adjacent Lattice World as the destination of the Out-Teeg. So far the search for Multi-World Travel (XWT) has proven fruitless, and all commerce and transport must labor under the Seven-Minute Limit of Single-World Travel (1WT). But the search continues, in nearly every Control Center occupied by man. Among the treasures to be had, if XWT is achieved, is the answer to whether the Lattice is indeed infinite.