ed, as have almost all living species The planet, severely depleted in water vapor, can no longer sustain the residual ocean mass Arrakis would probably not be suitable for man today if it were not for sandworms After recognition that an oxygen catastrophe had occurred on the planet, scientists were puzzled as to where the present oxygen came from Dragan et al solved die problem when they discovered that as part of its metabolic processes Shai-Huluci produces oxygen If this fact had been known earlier, the recent near-catastrophe in oxygen deprivation could have been avoided Man produced this near-catastrophe by interfering with the natural course of events Specifically, about five millennia ago, the famous planteologist Pardot Kynes started to plant the deserts of Arrakts, thereby transforming the planet into a site much more hospitable to hfe The process was very slow in getting started, for political and other reasons, and it was not uaul about 4,000 standard years ago that massive plantings began In hindsight, the caution that should have been taken is evident Vegetation requires water, but water kills sandworms Both vegetation and sandworms produce oxygen Atmospheric oxygen is rapidly depleted by chemical combination with rock on a planet as technically active as Arrakis Hence unless the rates at which vegetated areas are expanded and worms are killed are carefully controlled, the amount of oxygen can dip below the minimum required This dire event almost happened The first recognition that something was amiss occurred in 12820 A wildlife survey, completed that year, showed a dramatic de crease m the numbers of birds and mammals, and die general health of several species was poor Concurrently, scientific studies showed that the atmospheric oxygen content had dropped from 20 12% to 19 68% As a result, Lord Leto appointed a Planteology Commis sion to head a scientific task force Eight years were required to produce the final report In the meantime oxygen content had dropped to 19 23%, dangerously close to the critical level Humans were exhibiting signs ot oxjgen-deficienc} distress and several hundred deaths ha\e been attributed to this problem If local manufacture and large scale transport of oxygen for human consumption had not been started, the death toll would hdve been much higher Since that time the areas under cultivation and those reserved for desert have been care fully managed The atmospheric oxygen con tent reached a minium of 19 07% in 12840 and started to rise perceptably by 12845 Today the oxygen is controlled at 23 58%, and present plant life is sufficient to maintain this level J R Further references SANDWORMS Anra Satorima Adversit\ to Supremacy The Evolution of Shaihuludata (Loomar RTT Press) WN Dragan CD Urabo and AH Hautan Oxygen as Waste Product m Shaihuludata Science (Loomar) 70 442 453 ASSASSIN'S HANDBOOK Originally a third-millennium compilation of information on poisons to aid professional assass