bubbletubes

Bubbletubes, also known as pneumo-tubes or pneumatic tube transport, are a system of delivering small packages or documents through a network of tubes using compressed air or a vacuum. The system typically consists of a series of tubes, pneumatic carriers or "bubbles" that hold the items, and air compressors or vacuum pumps to propel the carriers.

The principle of operation is straightforward. An item is placed inside a carrier, which is then inserted into a terminal. A control system directs the carrier to its destination through the tube network. Air pressure is then applied to one end of the tube, pushing the carrier, or a vacuum is created at the other end, pulling the carrier. The carrier travels through the tubes at high speeds, reaching its destination in a matter of minutes.

Bubbletube systems were popular in the late 19th and early 20th centuries for rapid delivery within cities, particularly for mail, telegrams, and small parcels. Major cities like Paris, London, and New York had extensive networks. However, the advent of telecommunications, such as the telephone and fax machine, and later email, significantly reduced the need for physical transport of such items, leading to the decline of most bubbletube systems.

While largely obsolete for public use, pneumatic tube systems are still employed in specialized applications. Hospitals use them for transporting medication, lab samples, and blood. Banks utilize them for transferring cash and documents between tellers and vaults. Some modern industrial facilities also employ them for moving small parts or materials. The simplicity and reliability of the technology make it suitable for these niche uses where speed and direct point-to-point delivery are still advantageous.