Editing Jefferies Tubes (section)

==23rd century== 

In the 23rd century Jefferies tubes were still round and small, but they were better lit and weren't just a means to get around. They served many different functions and purposes. It was not uncommon to find many technicians and engineers tinkering inside them. 

Many diagonal tubes were scattered all throughout starships. These tubes were always densely connected with important system controls, relays, various conduits and vital engineering circuits. Some of these tubes led to crawl-way junctions, while some even continued on inside a nacelle pylon to one of the ship's actual warp nacelle. At the entrance of each tube were two red bars so a crewmen could pull him or herself inside. A soft, yet strong light was always emitted from the top and filled the entire tube. Certain tubes had multiple functions, while others had single functions like the tubes which were only designated engineering circuit bays. Each diagonal tube was equipped with stairs for crewmen to walk up or down. (TOS: "Charlie X", "The Doomsday Machine", "Journey to Babel"; ENT: "In a Mirror, Darkly, Part II"). 

The vertical tubes on a starship, also known as gangways, allowed manual access to decks both above and below. These particular tubes were easily accessible in the open hallway alcoves located on every deck. On the walls of these tubes there was a reflective material that perfectly illuminated the entire tunnel. The tubes were equipped with a single "three-way ladder" to allow more than one crewmen to climb or descend. (TOS: "Amok Time") 

The horizontal crawl-ways on starships allowed manual access to various parts of a starship. These tubes were also densely connected with important system controls and vital engineering circuits. Some of these tubes even led to the matter-antimatter reaction chamber. Every few feet, a bright light could be found shining down. Crewmen usually had to crawl while traveling in some of them due to the cramped size. Other horizontal tubes were still cramped, but crewmen could still walk freely up straight in posture. This was especially true late in the 23rd century. Late in the 23rd century, the horizontal tubes were extremely well lit with lights coming from both above and below. (TOS: "That Which Survives"; Star Trek V: The Final Frontier) 

On a starship, the Jefferies tubes had junction service crawl-ways. They served as interconnected points linking all the different tubes. On Constitution-class vessels, these junctions also gave access to critical starship systems like plasma flow regulators and warp and power relays. (ENT: "In a Mirror, Darkly, Part II")