GEOGRAPHY AND CLIMATE
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June 1959 was the wettest on record and the second wettest of all months since 1884. Almost 80% of the month's rain fell in the four days from the 12th to 15th when 724.6 mm. (28.53 in.) were recorded. This caused considerable damage to property and some loss of life.
There was above average rainfall during the rest of the summer which otherwise followed the normal pattern of hot and humid weather. The last three months of the year were all very dry and sunny. On November 19th the temperature rose to 89.2°F and broke the record for the November maximum.
During the year ten typhoons and nine less intense tropical storms were reported within the area for which the Royal Obser- vatory is responsible for issuing non-local warnings. Only two of these necessitated the hoisting of local storm signals in the Colony. The first was Tropical Storm 'Wilda' for which No. 1 Local Storm Signal was hoisted, and the second was Tropical Storm 'Nora' which gave strong gusty winds heralded by the No. 3 Signal. The total duration of the local warnings was 37 hours. The Strong Monsoon Signal was displayed eleven times for a total duration of 133 hours.
GEOLOGY
Hong Kong Island and the New Territories consist of numerous rugged and irregular islands with deeply dissected peninsulas. A general picture of the area is that of an upland terrain which has been invaded by the sea.
The uplands and mountains are eroded remnants of rock formations, in which relative resistance of rock and structure through differential erosion are clearly recorded. As the region lies within the northern limits of the tropics, frosts even on Tai Mo Shan are of the rarest occurrence, and hence weathering depends almost completely upon the chemical action of the atmosphere aided by the alternation of wet and dry seasons. Erosion is likewise due to water action which is at a maximum during the torrential rains of the summer monsoon. Again denuda- tion is aided by the excessive wind velocities of the typhoons and to a much lesser extent by the gentler breezes of the dry winter monsoon from Central China. Because of the destruction of forest growth and vegetation wrought by the agricultural population by