Watertube

The watertube was a Fremen device of wide application in the transfer of liquids on Arrakis. It had existed since the final stage of the Zensunni migrations, and its sophisticated design reflected the close attention the Fremen paid to small details. Behind a simple appearance lay careful engineering that reflected the extraordinary importance of water conservation in the desert.

Usage#

The watertube was used anywhere that liquids, especially distilled water, had to be transferred, since its design conserved the moisture so crucial to survival on Arrakis. Tubes ran in stillsuits between the catch-pockets and the mouth, and even between bodily orifices and the processing catches. They were built into the catchpockets of stilltents. The Huanui, or deathstill, used watertubing in its drainway and between its waiting basin and its flowmeter. Watertubes also appeared in literjons, in flowmeter spouts, and in portable windtraps.

Construction and function#

The body of the tube was a melange-based plastic with plyotyl mixed in to provide the needed flexibility. The plastic was liquefied and forced into a mold of plasteel, typically ten to fifteen centimetres square and two metres long. The mold consisted of a group of holes of differing diameters. A cap at one end allowed the extrusion of rods as long as the mold and of varying diameter, while a cap at the far end received the rods and helped maintain a consistent wall thickness in the tube being formed.

Partially cooled tubes were drawn from the molds and passed through a bonding vat, where the still-tacky inner surfaces, though not the cooler outsides, collected a crystalline solution. As that solution dried and bonded to the plastic, it formed the friction-release coating. With the active processes complete, the watertubes, by then resembling thin, limp cords of slightly different diameters, were taken to drying racks where they set up and cured.

Archaeological study#

A half-dozen molds were recovered at two sites on Rakis, leading scholars to speculate that tube walls could be varied in thickness depending on how the caps were fitted. No matter how the caps were installed the rods would penetrate the matching holes, but when the caps were rotated a quarter turn the relation of rod size to mold-hole diameter changed. This suggested that a small number of multi-purpose mold-and-cap combinations could have met different production needs for watertubes of differing flexibility and inside diameter. No finds confirmed this, nor the possibility that switching caps among molds could have yielded almost infinite varieties of characteristics. Some analysts held that such speculation overlooked the Fremen preference for keeping technology simple, while others argued that this very adaptability would reflect their sophistication.

The finds also showed an extraordinary uniformity of dimension, which suggested that some supplemental mechanism kept the rods perfectly straight inside the mold holes. The most common theory held that ultrasonic radiation, applied to the cooling plastic and plyotyl in the mold, stabilized the fluid and produced the macroscopic uniformity of the tube wall. Relics revealed trace samples of a flexible crystal almost inert at normal temperatures, found in significant amounts only near some bonding vats. Analysis indicated that this frictionless material had an intramolecular structure close to the later Pethlax and the prototype Frolmyr compound.