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In summer, the dampness of the air is excessive. Europeans suffer much from prickly heat and similar diseases. produced in consequence of the heat and dampness. The Chinese are also very subject to diseases of the skin, especially the different varieties of Tinea. Malarial fevers and diarrhoea are the worst hot weather diseases, the former chiefly of an intermittent type in summer. They are worst in August and September, when the Colony is under the influence of the high-pressure areas preceding and lying to the north of typhoons. In these areas the wind is light and the air descending, so that it is stifling, dusty, and probably full of bacteria. Want of sleep during such weather tends to produce anæmia from loss of appetite and thereby lays the foundation for many diseases such as diseases of the brain.

In autumn, the dampness of the air decreases, and the temperature falls often rather suddenly when the NE monsoon sets in. This causes affections of the chest and catarrhs, but Europeans enjoy almost an immunity from phthisis while to Eurasians this is an ever present scourge. Malarial fevers assume more frequently the remittent and bilious remittent type. Beri-beri is frequent among the natives, but cholera is never more than a minor evil in Hongkong.

In winter, dysentery-the dreaded scourge of the Pacific-occurs. This is the worst disease of the Chinese coast, and often leads to abscess of the liver. Small-pox is endemic and occasionally epidemic. Typhoid fever is very rare, but typho-malarial fevers are more common during the end of the winter and also in spring along the southern coast of China and Annam.

The most unhealthy places are situated in ravines between the hills, near marshy land or paddy fields. In such places malaria is deadly. Between one and two thousand feet up on the hills the air is pure and fever less common and of a milder type, which is as a rule easily cured by quinine. It is more agreeable to live in the upper regions although the air is frequently saturated with moisture.

Table I. exhibits the mean height of the barometer reduced to the freezing temperature of water, but not to the sea level, together with its annual and daily variations. For the months January- March inclusive, the diurnal variation is obtained from 9 years' observations only (1885-1893 inclusive), but the annual means depend on ten years' observations as the monthly means for January-March 1884 were obtained from readings made at 10 a. and 4 p. The data are of great practical importance as the diurnal variation although lessened in damp weather is not much influenced by storms. During the approach and continuance of a typhoon it is necessary to correct the readings for daily variation in order to know how much the mercury is falling or rising and when the lowest reading has been reached.

Table II. gives the mean temperature for each month of the year. The means for 1884 were obtained from thermometers in a Stevenson's screen, the readings being reduced to true air temperature. The hourly variation of temperature depends upon 9 years' observations only. The highest tempera- ture occurs between 1 p. and 2 p., and the lowest near 6 a. in winter aud about 5 a. in summer, that is, just before sunrise. The daily variation is least in March and greatest in December. The tem- perature of February is very different in different years being high when the amount of sunshine happens to be great and low if the amount of clouds is great. The mean temperature of the last five years was about 4° above the temperature of the first five years.

Tables III. and IV. give the mean humidity and the tension of aqueous vapour respectively, and the daily variations to which they are subject. For the first three months the daily variations depend upon 9 years' observations only. The humidity rises after sunset and remains nearly constant during the night, and is least about 1 p., varying inversely with the temperature, while the actual amount of vapour is greatest a few hours after sunset, and least shortly after sunrise.

Table V. gives the average amount of bright sunshine. It is least in March and steadily increases to a maximum in October, after which it steadily diminishes to its minimum. The daily maximum occurs shortly after noon and there is more sunshine in the afternoon than in the forenoon. There is

a slight decrease in the amount of sunshine near noon during the middle of the summer, which is due to a rather marked increase in the amount of clouds about that time. The entries of January and February are the means of 9 years only and the percentages of possible sunshine for these two months given in the last column are also derived from the observations of 9 years-1885-1893 inclusive.

Table VI. exhibits the mean rainfall. The hourly values for January and February are the means of 9 years only. It shows also the hourly intensity, which is greatest about noon, and least during the hours between sunset and midnight; while the rainfall itself is a maximum about 9 a. and a minimum about sunset. As more than two-thirds of the yearly rainfall occur during the months May-August the above remarks apply principally to that season, and a more extended series of observations would be required in order to show whether the same laws hold good for the drier months of the year. Most rain falls in June and least in November. The rainfall in October is very variable. Sometimes there is hardly any rain, while in other years there is heavy rain, usually owing to typhoons.

Table VII. gives the number of hours during a portion of which rain was registered. This was six or seven times larger in July than in November. Rain falls more frequently at and near sunrise than at sunset particularly in summer. The values for the first two months are the means of 9 years only.