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The water shortage having become very serious, on June 18R.A.F. planes from the R.A.F. base Kai Tak, dropped 6^ cwtsof powdered kaolin [fine white day] on cumulus cloud, with aview to producing rain. The experiments were suggested by aHong Kong resident and were sanctioned by the Navalauthorities at the request of the Hong Kong government, notwith any hope of producing rain, but to satisfy the public. Theresults were as expected.The last sentence, implying that the experiment failed, isinteresting in view of the report for 1929 of the Director,Mr. T. F. Claxton, who commented:A water famine resulted from a serious shortage of rain from themiddle of July 1928 to the middle of June 1929, when only 27inches of rain fell against an average of 71 inches. Disaster wasaverted by a rainfall of 3.8 inches between June 14 and 25,1929 ...Another experiment, using water seeding, was made inMay and June 1955. The preferred method of sprayingwater drops from an aircraft flying just above the cloud basewas considered too expensive - and impractical - for HongKong.Instead, three ground-based sprays were installed on theridge which runs east southeast from The Peak on HongKong Island. The sites were chosen because on most days inMay and June the sprays would be working close enough topassing convective clouds to be effective.While the experiment provided valuable informationabout rainfall in general, it also showed that water seeding ofcumulus clouds did not increase rainfall in Hong Kong.Climatological information services:Apart from providing data for the weather forecastingand tropical cyclone warning services, the Royal Observatory'sclimatological information service is also operated tomeet the needs of shipping, aviation, engineering, industry,recreational activity and the public.The information provided includes data collected at thesurface and in the upper air. Daily, weekly, monthly and112