A DHARMA message Tube
Pneumatic tubes are physical transport systems in which cylindrical containers are propelled through a network of tubes by compressed air or by a vacuum. The containers are vehicles for transporting physical objects. Pneumatic tubes were also briefly considered for a subway-like transportation of people, as well as a long-distance postal service. Pneumatic tubes are also known as capsule pipelines.
Tubes seen behind Jack.
The Pearl station had a pneumatic tube system. In the Pearl Orientation video, Mark Wickmund (a.k.a. Pierre Chang) instructed that the pneumatic tube was to be used to transport data collection notebooks back to "us".
- Capsu.org History on capsule pipelines