a.Dust deposited after each storm was highly charged. Also, grain surfaces contained absorbed water vapor.
b.The number of negative electrons and positive ions was initially about equal within the dust mass.
c.The electrons attached themselves to the highly polar water-vapor molecules.
d.The water-vapor molecules migrated upward along the atmospheric density gradient. The ultraviolet rays then desorbed the water vapor, returning it to the atmosphere, together with the negative charges.
e.The positive ions were tightly bound to the distorted surface lattice of the dust grains and remained behind.
f. As a result the dust had a strong and highly stable positive charge. The repulsive electrostatic forces almost equaled the gravitational forces, hence the fluid-like behavior.
g.The dust layer built up in depressions and chasms after this fashion until they were filled. Of course as the layer thickness increased, the weight of the overburden caused compaction. Hence the quicksand-like behavior was confined to the upper five meters (approximately) of the deposit.
The above phenomena were not observed in exposed areas since any charge inequality on dust deposited there was quickly neutralized by subsequent motion over the surface and prolonged exposure to ultraviolet. Of course neutralized dust was present in the chasms and basins, but it accounted for only a small percentage of the total. The charged zones had no influence on the behavior of neutralized dust or sand moving over them. In fact the first few tenths of a millimeter of the dust oceans was neutralized by ultraviolet exposure.
Pachtra is generally given credit for discerning the mechanism responsible for the sound emitted by drum sand7. The record is a bit fuzzy here, but the academic discussion of who should receive credit is of little import and as Ghralic states, "It is the advancement of our knowledge that counts." The use of the terminology "drum sand" was unique to Arrakis, but sound-emitting sands have been found on many Neta-type planets, particularly those of the C and 50 to 60 subclassifications. Local nomenclature depends upon the nature of the sound emitted, natives almost invariably naming the sands after the tonal quality closest to that of an indigenous musical instrument.
Most musical sands produce a single tonal sound which decays exponentially with time after being stepped upon or otherwise impacted. A second step produces a similar sound with similar monotonic decrease in intensity. Drum sand, however, emits a series of low-frequency beats from a single step. These beats do die out exponentially, but the pulsating (drumming) character is quite distinctive.
It was known long before Hohshas's time that four conditions are necessary for a sand to sing. First, the sand grains must be of approximately equal size. Second, the grains must be bonded together. This bonding is most commonly produced by the chemical deposition of water-soluble salts on the grain surfaces. Third, the packing density must be uniform. Finally, the underlying bedrock must be essentially parallel to the sand surface. Any impact produces vibrations, but when the above conditions are met this impulse can create resonance and a tone is produced. The sand layer vibrates as a unit. If the ratios of mean grain spacing to grain diameter and mean grain spacing to bed thickness fall within prescribed limits, the tone will be audible to human ears. These several conditions are not normally met and thus singing sands are not particularly common. But if these conditions are met then we have an excellent analog of a musical instrument, albeit without the marvelous tonal and expressive capabilities of true musical instruments (including the human voice).
Pachtra recognized that under certain conditions the ratios noted above could have values that resulted in: a pattern of constructive and destructive interference in the sound waves. This would cause a pulsating sound from a single impact or step. Pachtra was not only a masterful applied mathematician but also an excellent experimentalist. He spent several years on Arrakis performing on-site investigations in spite of the obvious dangers. This combination of field, experimental, and theoretical research has endeared him to planetologists (actually to all scientists). It is unfortunate that his brilliance and courage were not recognized until recently.
MAGNETIC FIELD. Arrakis has its own magnetic field (see ARRAKIS — GEOLOGY for details). However, Canopus emits an abnormally high flux of charged particles with imbedded magnetic-field segments. This severely contracts the planet's own magnetic field and allows particles to impinge directly on atmospheric molecules. No known effect on Arrakis weather has been proven to be a result of this interaction. However, magnetic disturbances make the main field unreliable for navigation. Alternative means for direction finding, such as the paracompass, were developed to overcome this problem. Today our techniques far exceed these rudimentary navigational efforts.
WEATHER PREDICTION. Modern techniques make weather prediction by the Arrakians (about 5000 years ago) seem extremely primitive. However, their method was well suited to the conditions on Arrakis. Indeed, the predictions were remarkably accurate and thus merit note. Who would believe that emplacement of poles, without sophisticated monitoring equipment, could predict weather? But it did work on Arrakis because all weather phenomena in inhabited regions were associated with dust storms. This simplified the problem over that on other planets. A line of poles (or double line) was placed on the lower slopes of garres and ridges. Each line ran along the direction of the slope. Siting was particularly important. The slope had to face a large open area as well as the direction from which storm winds blew, had to be devoid of large boulders which could produce eddies, required a slope angle of 15 ± 5 degrees, and had to be backed by a steep walled topographic feature rising at least 500 meters above the surroundings. When these specific conditions were satisfied, the upslope winds impacting the topographic feature were not only deflected upward suddenly but also crested a wind shadow zone on the upwind side of the obstacle. This is not meant to imply that a calm prevailed within the shadow zone. Rather, with the specific geometry chosen, the winds are slightly less with the degree of difference increasing as wind speed increased. Poles within the shadow zone were thus slightly less exposed to wind action than those down the slope.
The prevailing winds always carried dust. The Fremen chose the most easily abradable material they could find (known today as amborite) to coat the poles. This coating would be slowly worn away by even the lightest of winds. Measurement of the mass loss each day in itself gave the integrated product of wind speed and dust content to an accuracy somewhat greater than could be determined with instruments in existence at the time. By taking the ratio of this product for the down-slope poles to the shadow-zone poles, one obtains a wind-speed ratio. The accuracy of this determination far exceeded capabilities of other instruments, and even today is better than some of our present instruments (manufacturer claims not withstanding).
One can calculate wind speed from the wind-speed ratio and knowledge of the surface geometry, but there is no record that the Fremen did so or had the mathematical knowledge to do so. However, there was no need to make this calculation since the speed ratio was all that was needed for weather prediction on Arrakis. It is well established that Arrakian storms were preceded by an extremely small decrease in integrated wind speed (also the speed ratio, which in that case was directly proportional to wind speed). On most other habitable planets this decrease is large, readily noticeable, and is commonly called "the calm before the storm." On Arrakis, the decrease occurred one day be fore a minor storm, increasing to two days for a major storm, and five days for the greatest Coriolis storms. The size of the storm to be expected was proportional to the square of the magnitude of the decrease. It is still a source of wonder to many scientists how the Fremen were able to discern these relationships.
J.R.
NOTES
1Pardot Kynes, "Atmosphere of Arrakis," Bulletin of Planetology, NS 127:135-55.
2Marta Ptahtercicah, "Water Vapor in the Life Cycles of Organisms," Imperial Biology Papers, Ser. 5, 15:106-68.
3L.L. Nefad, "Rotation and Corio
lis," Bull. Planet., OS 784:86-117.
4Joon F. Hohshas, "Internaction of Temperature, Rotation, and Radiation in Coriolis," Bull. Planet. NS 1301:48-68.
5Dorit Pachtra, "Storm Effects on Arrakis," Bull. Planet., OS 1630: 230.
6R. V. Asterák, "Macro Effects in Charged Dust Particles," Soil Science (Caladan), 27: 422-99.
7Dorit Pachtra, "Transmission of Sound in Sand Under Conditions Unique to Arrakis," Bull. Planet., NS 5:80-108.
Further reference: Th. Zed Ghralic, Arrakian Climatological Studies from Atreidean Times to the Present, Meteorological Forum, whole issue 59.
ARRAKIS, Ecological Transformation of
Pardot Kynes (10121-10175) was appointed Planetologist for Arrakis by Elrood IX in 10149. The 28-year-old ecologist was considered too young for the post by his enemies, and overdue such an appointment by his supporters. Public opinion aside, Kynes had already proven himself one of the leading practitioners in his field with his handling of the Cartha outbreak on Ecaz1, and was Elrood's logical choice.
From his arrival on Arrakis, Kynes's relations with the Harkonnens, then holders of that fief, were not good. The ecologist cared nothing for politics or intrigues; he simply wished to be left alone to study the desert planet and to report his findings to his emperor. This the Harkonnens constantly interfered with, not least by their insistence that one or more of the House guard accompany Kynes at all times. Kynes, in turn, protested the restrictions this placed on him, avoided them whenever possible, and determined that the rulers of "his" planet would obtain as little information from him regarding its workings as he could provide.
Another division between the two was the Harkonnen's insistence on viewing Arrakis as a hellhole, fit only for producing its priceless spice and helping to keep its native workforce subdued. Kynes, on the other hand, soon became caught up in a vision: he became more and more convinced with each new study he conducted that Arrakis could be transformed into a gentler world, one on which humans could live without the constant threat of death from thirst haunting them.
By 10151, he had decided that only the Fremen, already capable of meeting the desert on its own terms, could possibly help him implement his scheme. In addition to their own innate ecological sense, the Fremen were the only people on Arrakis who did not bow in terror to the Harkonnens. They paid no fai, no water tribute, to the tyrants, and they were not above guiltlessly killing any outsiders foolish enough to invade their privacy. He would convert the Fremen, Kynes decided, as soon as the opportunity to enter one of their sietches presented itself.
In the spring of that same year, on a rare walking excursion without his Harkonnen guards, Kynes stumbled upon his entree. Behind the section of the Shield Wall nearest the village of Windsack, he found half a dozen fully armed and shielded Harkonnen bullies toying with three Fremen youths, evidently planning to kill them leisurely, for sport. Kynes waded into the fray and killed two of the Harkonnen men with a slip-tip before anyone was aware he had joined the battle. By this time, the Fremen had downed two of the bullies on their own, but one of the youths was down as well, with a severed artery. Kynes dispatched one more Harkonnen, then, leaving the single survivor to his fate at the hands of the two Fremen, gave the third boy the medical attention he needed.
To the youths, not yet experienced in the ways of brutal necessity, the ecologist represented a water burden they did not know how to repay. Confused, they took Kynes back with them to their unnamed sietch overlooking Wind Pass. Let the elders decide what was to be done with this most uncommon Imperial servant!
Once in the sietch, Kynes felt himself completely in his element. He lectured the amazed, Fremen on a number of subjects — the best ways of anchoring dunes with grass, with fruit-bearing trees might best be planted in the resulting greenbelts, pros and cons of qanat (open-trench) irrigation — but always returned to one magic topic: water. The Fremen listened, even as they debated what to do with this insane stranger who had saved three of their number, and marveled at his complete disregard for his own safety.
Kynes was clearly admired by most of the troop, and it was for that reason that his death sentence was delivered with a touch of regret. Still, the security of the sietch overrode all other considerations, and Uliet, one of the troop's most experienced fighters, was sent with a consecrated knife to carry out the sentence. Two watermen followed him, prepared to release the intruder's water for use by the sietch.
It was an efficiency of which Kynes might have approved, had he taken time out from his lecturing to pay attention. As it was, the ecologist merely paused between sentences when Uliet approached. "Remove yourself," he told his appointed executioner, then turned, leaving his back open.
Uliet hesitated, and in that moment of hesitation, made a decision that would change the destiny of his people. Instead of striking the ecologist, he took three steps and fell on his crysknife, "removing" himself as ordered. The stunned watermen carried him off to the deathstill, and Kynes continued his lecture as if nothing had occurred.
Not one member of the troop entertained the notion of questioning such an obvious message from Shai-Hulud. Kynes was meant to lead them; they, to follow him.
Beginning with a one kilometer square area located in the deep desert (around 40° south latitude), Kynes ordered that the tribes begin the work of settling into the hitherto-uninhabited region. The first tribe sent out died, almost in its entirety, leaving only a pair of messengers to report back. Kynes listened to them, took careful notes, and sent out another group, this one better prepared. Numbering one hundred fifty on departing for the south, the tribe was reduced by half within the first six months. But the settlement was established.
Kynes, during this time, was not idle. Under the unsuspecting noses of his Harkonnen overseers, he smuggled desert Fremen into his Biological Testing Stations. The Fremen studied, conducted tests, took tools and equipment back to their sietches with them for use in setting up hidden windtraps and water basins. With agonizing slowness, the basins began to fill, the water gleaned from the air being supplemented by that from the death-stills. With the sole exception of combat water, which by Fremen law belonged to the victor of a hand-to-hand fight, all water obtained by the sietches found its way into one of these basins. No Fremen would drink of it, no matter his extremity, on pain of losing his soul. It was the Water of Paradise, sacred beyond words.
The Harkonnens knew nothing of Kynes's plan, nor of his Fremen. Behind the ecologist's back, jokes were made about his pleasure in associating with the "desert scum" — Jokes which became even more vicious when it was discovered that he had taken Mitha, a woman from Sietch Tabr, as wife — but no one dared mock him openly. Imperial servants, whatever their peculiarities, had power. Kynes had more than most, based on his popularity with the emperor and the natives of Arrakis. He was given a wide berth.
The first core samples taken from the trial zone, in 10152, revealed that the sand itself could provide most of the nutrients the Fremen's plantings would require, since much of it was produced as a byproduct of sandworm digestion. Dust presented a very real danger: even a relatively mild sandstorm could bury the trial zone. It was decided that some old, reasonably stable dunes would give the plantings their best chance — provided the problem of holding down the dust could be resolved.
While one group of Kynes-trained Fremen wrestled with the sand-fixing puzzle, others were studying weather patterns, area climates, and the myriad other pieces of the ecological puzzle.
Particularly curious was the existence of a few plants the Fremen discovered and cultivated. A rare native root plant, for example, which grew above the 2500-meter level in the northern temperate zone, was often called "Gift to the Thirsty" because of its high water content: a tuber two meters long yielded half a liter of water, many times over the moisture that could be obtained from an equivalent weight in other vegetation. The water, the Fremen assumed, was not being drawn out of the atmosphere; somehow, the tubers were responsible for pulling it in. Where was
it found?
Kynes worked like a madman, correlating data between groups, performing his own research, and doing the social dances required to keep the Harkonnens — and the emperor — ignorant of the real purpose of his work. If the strain tired him, he never revealed it to his Fremen, who had come to consider him one of their umma, the brotherhood of prophets. It made no difference to Kynes what he was called, so long as progress was made.
Two last discoveries, arrived at within a month of one another, provided the data needed to begin the real work. The first gave confirmation that what they planned to do was indeed possible: the verification by Kynes himself of the existence of a salt pan in the deep bled. This proved that there had been open water on Arrakis at one time; what had been, could be again.
The second discovery concerned the sand-worm. These mighty creatures began their lives as sand plankton, then matured into the sandtrout form before becoming worm, It was the sandtrout phase — in which the "water-stealers" swam freely through the sand and sealed off all available water in the porous lower strata — which most worried Kynes. If these animals could seal water so effectively, what was to prevent them from completely drying out any area his Fremen chose to plant?
His fears were proven groundless when captured sandtrout were loosed in one of the Testing Station gardens. Try as they might, the sandswimmers could not perform their usual function in an environment choked with plant roots. They exhibited two reactions: flight and death.
More groups of Fremen were sent out, to establish other trial zones along the 40° line. With them they carried a variety of sophisticated drilling equipment and sandtrout-proof sheaths, as well as the usual material for constructing windtraps and temporary holding basins. If there was water to be found under the sand in their areas, they were prepared to dig for it; if not, the windtraps alone would have to suffice.
The Dune Encyclopedia Page 7
